S P E C I A L P A P E R S I N P A L A E O N T O L O G Y N O . 7 2

L O W E R J U R A S S I C F L O R A S F R O M H O P E B A Y A N D B O T A N Y B A Y , A N T A R C T I C A

B Y P . M . R E E S a n d C . J . C L E A L

with 22 plates, 2 tables and 7 text-®gures

T H E P A L A E O N T O L O G I C A L A S S O C I A T I O N L O N D O N

October 2004

C O N T E N T S Page

ABSTRACT 5 MATERIAL AND METHODS 5 SYSTEMATIC PALAEONTOLOGY 8 AGE OF THE HOPE BAY AND BOTANY BAY FLORAS 72 PALAEOENVIRONMENT AND PALAEOCLIMATE 78 CONCLUSIONS 82 REFERENCES 83

ABSTRACT. Hope Bay and Botany Bay, Graham Land, Antarctica have yielded two of the most diverse ¯oras known from the Jurassic. Because of its high diversity, as well as its early discovery and description Cby T. G. Halle in 1913), the Hope Bay ¯ora has served as a taxonomic standard for studies of other Mesozoic ¯oras from Gondwana. This paper presents a major revision of the Hope Bay ¯ora, based on extensive subsequent collections. A nearby ¯ora from Botany Bay is described for the ®rst time. Thirty-seven species are now recognised in the Hope Bay ¯ora and 32 from Botany Bay. The ¯oras are closely similar; 80 per cent of the Botany Bay species also occur at Hope Bay. They are shown here to be Early Jurassic, which contradicts the results of previous studies that suggested a Late Jurassic or earliest Cretaceous age. The revision of their age has special signi®cance for our understanding of the Mesozoic geological history of the Antarctic Peninsula. It also highlights the need for reappraisal of a number of other Mesozoic Gondwanan ¯oras that had been dated mainly on their close similarity to the Hope Bay ¯ora. The taxonomic work has resulted in establishment of a new combination, Taeniopteris taeniopteroides, and emendation of the diagnoses of Coniopteris oblonga, Sphenopteris nordenskjoeldii, Sphenopteris pecten and Komlopteris indica.

KEY WORDS: Jurassic, palaeobotany, leaf impressions, Antarctica.

H O P E Bay, northern Graham Land, Antarctica CPl. 1 ®g. 2) has yielded one of the most diverse ¯oras known from the Mesozoic. Its great diversity, as well as its early discovery and description, has made it a standard for ¯oristic and biostratigraphical studies on Mesozoic Gondwanan ¯oras. It is also important for understanding volcanic arc evolution and palaeogeography of the northern Antarctic Peninsula. The only complete descriptions published to date are by Halle C1913) and Gee C1989), based on 220 rock samples collected during the Swedish 1901±1903 expedition. Halle C1913) described 59 species, with two forms of unknown af®nity, which Gee C1989) revised to 43 species. Subsequent larger collections from Hope Bay were made by British expeditions in 1945 during Operation Tabarin and in 1946 by W. N. Croft as part of the Falkland Islands Dependencies Survey CFIDS), but these were not described. Material was also collected but not described from the nearby Botany Bay locality CPl. 1, ®g. 1), by W. N. Croft CFIDS, 1946), and by G. W. Farquharson as part of the 1979/1980 British Antarctic Survey CBAS) ®eld programme. Further material was collected by one of us CPMR) as part of the 1986/1987 BAS ®eld programme. The British collections have enabled a comprehensive account of these important ¯oras. The results formed part of a doctoral thesis CRees 1990), and some aspects have been published previously CRees 1993a±d; Rees and Cleal 1993). Dipteridaceaen ferns from Hope Bay and Botany Bay were described by Rees C1993a), and Morel et al. C1994) subsequently documented other Botany Bay specimens. However, what follows is the ®rst description of the entire Botany Bay ¯ora as currently known and the ®rst complete revision of the Hope Bay ¯ora, using new material, since Halle's C1913) monograph.

M A T E R I A L A N D M E T H O D S This study is based on over 2000 rock samples from Hope Bay and Botany Bay CPl. 1; Text-®g. 1) collected between 1945 and 1987 mainly by FIDS and BAS expeditions. Some are still stored in the BAS collections at Cambridge, but the majority are now housed in The Natural History Museum, London. Nevertheless, except for some previously ®gured plant specimens, they are all still stored under their original BAS registration numbers, with a D. pre®x. Where specimens are listed in the Systematic Palaeontology section, they are only those that are ®gured and used in the descriptions. The suf®xes A and B refer to the upper and lower surface of each rock sample. To ensure complete documentation, one of us CPMR) has also examined the Halle Collection in The Natural History Museum, Stockholm. The leaf ¯oras are preserved as impressions and coali®ed compressions. Attempts to recover identi®able palynomorphs from the plant beds at Hope Bay and Botany Bay have been unsuccessful CT. H. Jefferson in Farquharson 1984; D. Guy-Ohlson in Gee 1989; Rees 1990). In addition to diagenetic processes, the Hope Bay plant beds have been affected by contact metamorphism Cto biotite grade; Farquharson 1984), so no microscopic characters Ce.g. epidermal cell structures) are preserved. Only one specimen from Botany Bay showed epidermal detail CPachypteris indica; Pl. 10). Latex and acetate replication of impression surfaces, transfer preparation and scanning electron microscopy were used on other specimens, but did not contribute any signi®cant information.

[Special Papers in Palaeontology, 72, 2004, pp. 5±90, 22 pls] q The Palaeontological Association

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TEXT-FIG. 1. Map of Hope Bay and Botany Bay. Inset shows an Early Jurassic palaeogeographical reconstruction Cafter Rees et al. 2000) showing the location of these Antarctic sites. Also shown, for broad comparative purposes, is the location of the Middle Jurassic Stones®eld ¯ora CCleal and Rees 2003).

The specimens were studied and photographed using standard binocular microscopy, ®bre optics unidirectional lighting Cto enhance venation details), cross-polarised light or immersion in industrial alcohol Cto enhance contrast between the fossil and its surrounding matrix). Specimens that proved dif®cult to photograph using these more straightforward techniques were coated with a thin layer of ammonium chloride. Specimen frequencies were measured in the Botany Bay sequence using a 0´5-m quadrat. This, combined with sedimentological observations, has enabled lithological controls on the distribution of each plant species and changes in species associations to be determined Csee Text-®g. 7).

E X P L A N A T I O N O F P L A T E 1 Fig. 1. View of Botany Bay, northern Graham Land, looking west. The plant beds of the Botany Bay Group are in the foreground. Church Point, the mountain to the left of the picture, is 337 m high. Fig. 2. View of Mount Flora, Hope Bay, northern Graham Land. The man CPaul Wood) is standing on the contact between the plant-bearing beds of the Botany Bay Group Cbelow) and the volcanic rocks of the Antarctic Peninsula Volcanic Group Cabove).

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REES and CLEAL, Botany Bay and Mount Flora, Hope Bay

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:03 ALDEN 8 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Systematic descriptions follow standard format. Synonymy lists have been annotated using the same scheme as in Cleal and Rees C2003): *, publication of the protologue of the basionym; T, any published illustrations of the type; and }, any published records of specimens from Botany Bay or Hope Bay. Otherwise, only references that are critical for understanding the taxonomy of the species, especially as it relates to the Botany Bay and Hope Bay material, are included. The taxonomic hierarchy used is based mainly on that given in Cleal and Thomas C1999).

S Y S T E M A T I C P A L A E O N T O L O G Y

Division EQUISETOPHYTA Class EQUISETOPSIDA Order EQUISETALES Family EQUISETACEAE Richard ex Michaux, 1803 Genus EQUISETUM Linnaeus, 1753

Type. Equisetum ¯uviatile Linnaeus, 1753.

Remarks. Watson and Batten C1990) have argued that equisetalean fossils that cannot be con®dently assigned to Equisetum should be placed in Equisetites Sternberg. However, we can see no obvious reason why our material is not cogeneric with the living plants and have therefore followed Harris C1961) and referred them to Equisetum.

Equisetum laterale Phillips emend. Gould, 1968 Plate 2, ®gures 1±4 *1829 Equisetum laterale Phillips, p. 153, pl. 10, ®g. 13. }1913 Equisetites approximatus Halle, pl. 1, ®gs 6±14; text-®g. 1. 1961 Equisetum laterale Phillips; Harris, p. 20. 1965 Equisetites patagonica Herbst, pl. 1, ®gs 1, 3; pl. 2, ®gs 9±10. 1968 Equisetum laterale Phillips; Gould, p. 153. 1987 Equisetum laterale Phillips; Shuying, pl. 2, ®gs 5, 8; pl. 3, ®gs 5±6, 8±9; text-®g. 6. }1989 Equisetum laterale Phillips; Gee, pl. 1, ®gs 3±6. See Harris C1961), Gould C1968) and Gee C1989) for other synonyms.

Holotype. Specimen from the Middle Jurassic of Yorkshire ®gured by Phillips C1829, pl. 10, ®g. 13). According to Pyrah C1979) the specimen is not in the collections of the Yorkshire Museum or Whitby Museum, and its current location is unknown.

Material. Hope Bay: D.34.7, D.37.1a, D.37.1c, D.37.2, D.37.7, D.37.9, D.39.6. Botany Bay: D.8878, D.8932.3A, D.8935.2, D.8935.5, D.8935.8B, D.8936.3, D.8955.1, D.8965.14A, D.8965.25A, D.8965.32B, D.8974.2, D.8975.1c, D.8975.4B.

E X P L A N A T I O N O F P L A T E 2 Figs 1±5. Equisetum laterale Phillips emend. Gould. 1±2, 4, Hope Bay. 1, D.37.1a; stem with widely spaced leaf sheaths and nodal diaphragm; ´ 0´5. 2, D.37.9; stem fragment with closely spaced leaf sheaths; ´ 1´5. 4, D.37.1c; nodal diaphragm showing wheel-like structure; ´ 3. 3, 5, Botany Bay. 3, D.8975.4B; stem and nodal diaphragm; ´ 1´5. 5, D.8937.15B; probable Equisetum cone fragments Cpossibly of Equisetum laterale), showing sporangio- phore heads; ´ 7.

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Description. Unbranched stems with nodes marked externally by position of leaf sheath bases. Nodes not swollen. Stem internodes 4±30 mm wide Ctypically 10±20 mm); measured from nodal diaphragms, 3´5±8´5 mm. Internode length Cmeasured between bases of neighbouring leaf sheaths) 7±70 mm Ctypically 10±20 mm). Leaf sheaths typically spaced so that each internode is exposed, only occasionally overlapping slightly. Total number of leaf sheath segments Cestimated from nodal diaphragms) 18±26. Stem internodes grading upwards into the leaf sheath bases, sheath typically expanded distally, stem diameter increasing slightly from that at the node Cˆ base of leaf sheath). Sheath length Cincluding teeth) 6±14 mm Ctypically 8±12 mm). Sheaths divided at their bases into leaf segments separated by commissural furrows. Wholly preserved individual leaf sheath segments strap-shaped, lacking a midrib, with entire margins and acute apices. Leaf segments separated distally into free teeth for c. 50±80 per cent Ctypically 60±75 per cent) of their length. Leaf tooth length 4±10 mm Ctypically 6±9 mm). Leaf segment basal width 1´0±1´5 mm. Leaf segment margins parallel or subparallel from their bases to c. 20±50 per cent Ctypically 25±40 per cent) of distance to apex, then converging Cas free teeth) at an acute angle to pointed apex. Each leaf tooth margin bordered by an inwardly sloping commissural ¯ange, which widens distally. Maximum observed width of distal ¯ange 1 mm. Commissural furrow in the lower part of sheath consisting of a narrow groove, which also widens distally and which separates the commissural ¯anges of adjacent leaf teeth. Circular nodal diaphragms are wheel-like, typically comprising a central hub, radiating spokes and a narrow rim. They are preserved either ¯at or depressed in the matrix with an elevated central region, although one diaphragm has a pitted surface and lacks wheel-like features. Diaphragm diameter 3´5±8´5 mm Ctypically 4±6 mm). Spoke length 1´0±2´5 mm, 18±26 spokes per diaphragm. Length of spoke 45±90 per cent of diaphragm radius Ccentral hub forms 10±55 per cent of diaphragm diameter). Diaphragm rim c. 1±2 mm wide.

Remarks. Whether fossil equisete remains should be assigned to Equisetum or Equisetites has often been discussed. Harris C1961) and Gould C1968) advocated the use of Equisetum as no signi®cant morphological difference has ever been proved between the extant and fossil forms and those differences that there are Ce.g. certain features of the spores) probably have a taphonomic explanation Ce.g. Gould 1968, p. 156). The best way of determining the number of leaf segments in the sheath of E. laterale stems is to count the number of spokes in the nodal diaphragm CHarris 1961, pp. 21, 23; Gould 1968, pp. 159, 163). Gould also found that the true stem diameter might be measured from nodal diaphragms. At Hope Bay and Botany Bay, nodal diaphragms of E. laterale were found isolated in the rock matrix, in association with stem fragments Ce.g. Pl. 2, ®gs 3±4) or were occasionally seen on ¯attened stem internode surfaces. From this, it was evident that compressed stems only showed 30±50 per cent of the true numbers of leaf segments Cbetween 5 and 12) depending upon the degree of compression. The present specimens compare with the Middle Jurassic specimens from Yorkshire, assigned by Harris C1961) to E. laterale, although they are much more variable in characters such as stem width and internode spacing. The Australian specimens attributed to this species by Gould C1968) have the same range of measurements for all characters as the Hope Bay and Botany Bay material. E. laterale resembles anatomically preserved stems of E. rajmahalense from the Rajmahal Flora of India CSahni and Rao 1933; Bose and Sah 1968; Person and Delevoryas 1982). However, the latter has nodal diaphragms comprising small cells Cˆ `pits') rimmed by tubercles, with no trace of the wheel-like structure seen in E. laterale diaphragms. Systematic sampling at Botany Bay has shown that E. laterale is typically preserved in siltstone and shale, often in horizons where no, or few, other plants are present Csee Rees 1993d, and this paper) and this is probably also the case at Hope Bay. The Hope Bay and Botany Bay Equisetum plants probably grew near where they are preserved, along shallow lakes, streams, or marshes, as with many other species of the genus.

Probable Equisetum cone fragments Cpossibly of Equisetum laterale) Plate 2, ®gure 5 Material. Botany Bay: D.8937.15B, D.8956.43B.

Description. Clusters of spirally arranged sporangiophore heads. Up to at least 20 sporangiophore heads per cluster, margins of one head in contact with those of neighbouring heads. Long axis of head c. 2´5±2´8 mm, short axis 2´2±2´6 mm. Each sporangiophore head typically with six sides Cˆ faces), occasionally ®ve; sides of unequal length

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Ce.g. ranging from c. 0´5 mm to 2´0 mm long on same head). Heads often detached, single in matrix, each comprising a central boss ¯anked by pyramid-like segments, corresponding to the sides; central boss 0´6±0´7 mm long by 0´7±0´8 mm wide.

Remarks. These specimens are fragmentary and preserve neither ®ne details nor spores. They are similar in size and shape to cone remains from the Yorkshire Middle Jurassic ¯ora illustrated as E. columnare CHarris 1961, p. 18) CE. laterale cones are not known from the Yorkshire ¯ora; Harris 1961). Cones of E. laterale from Australia CGould 1968) have smaller sporangiophore heads Cc. 1 mm in diameter) than those from Botany Bay. However, Gould suggested that the former may have been small examples of the species, as they were borne on ¯attened stems only 3±4 mm wide, which is much narrower than the Hope Bay and Botany Bay specimens. Although the cone fragments from Botany Bay are associated with E. laterale stem fragments, none was in attachment and so can only be assigned tentatively to that species.

Division PTERIDOPHYTA Class FILICOPSIDA Order FILICALES Family DIPTERIDACEAE Seward and Dale, 1901 Remarks. Dipteridaceaen genera are readily separated based on their gross morphology and venation Ce.g. OÃ ishi and Yamasita 1936; Arrondo and Petriella 1982). Hausmannia and Clathropteris leaves are entire or only weakly Cand often irregularly) segmented, with typically rectangular vein-meshes. The other genera have generally more polygonal vein-meshes, and the lamina segmentation is deeper and more consistent, producing more distinct frond members that are separate to their bases and more or less pinnate. Thaumatopteris, Camptopteris and Dictyophyllum are characteristically once-pinnate Cwith pinnules arising directly from each frond-member), whereas Goeppertella is twice-pinnate Cwith each frond- member bearing pinnae, each pinna bearing pinnules). Also typical for Goeppertella is the attachment of the lowermost basal pinnule on the main rachis Ce.g. Pl. 3, ®g. 1) and the frequent presence of intercalated pinnules Csee OÃ ishi and Yamasita 1936). Rees C1993a) recognised two genera, Hausmannia and Goeppertella, in the material from Hope Bay and Botany Bay. Incomplete specimens identi®ed as Dictyophyllum by Halle C1913), Gee C1989) and Morel et al. C1994) are in fact Goeppertella Csee Rees 1993a, and below). There are three issues here: frond polymorphism, the extent of frond completeness, and the range of species variability determined by the number of available specimens. Polymorphism is a common feature of fern and pteridosperm fronds and has already been documented in Archangelskya furcata from Hope Bay and Botany Bay CRees and Cleal 1993). Clearly, fragmentary material provides only a partial insight on variation in the complete frond. The dipteridaceous specimens described by Rees C1993a) are more complete than those of Halle C1913), Gee C1989) and Morel et al. C1994). Also, Rees based his descriptions on more specimens, which showed a greater range of characters, linked by intermediate forms.

Morphogenus GOEPPERTELLA OÃ ishi and Yamasita, 1936 Type. Goeppertella microloba CSchenk) OÃ ishi and Yamasita, 1936.

Remarks. Fragments of once-pinnate Goeppertella pinnae can be dif®cult to separate from frond-members of Dictyophyllum. All unequivocally identi®able specimens from Hope Bay and Botany Bay clearly belong to Goeppertella and so the similar but fragmentary material is also assumed to belong there. Although similarly fragmented and sterile specimens from Argentina and Australia have been assigned to Dictyophyllum, it is impossible to be sure that they are not Goeppertella without more complete material. This is important because of the stratigraphical value of these two genera, which have not been recorded reliably from strata younger than Early and Middle Jurassic respectively Cdiscussed in detail later).

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:03 ALDEN 12 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Goeppertella jeffersonii Rees, 1993a Plate 3, ®gures 1±2 *}1993a Goeppertella jeffersonii Rees, p. 639, pl. 1, ®gs 1±3; pl. 3, ®g. 4; text-®g. 3B. }1994 Dictyophyllum atuelense Morel et al, ®g. 2A, pl. 1, ®g. 1.

Holotype. V.63595; provenance Botany Bay.

Diagnosis Cfrom Rees 1993a). Frond-member bipinnate; pinnae alternating regularly with well-de®ned rachial pinnules. Shape and size of rachial pinnules comparable to that of pinnules on pinna rachis; pinnules wedge-shaped, slightly falcate, 4±13 mm long ´ 2±8 mm wide, curving forwards near their tips towards pinna apex. Pinnule apices acute to subacute, margins typically entire. Venation reticulate, poorly ranked, veins dividing to form polygonal vein meshes, ®rst laterals branching uniformly from main vein, pattern not disrupted by rachial veins.

Material. Botany Bay: V.63590±V.63597.

Description. For a detailed description of this material, see Rees C1993a, p. 642).

Remarks. This species, described from Botany Bay by Rees C1993a), has the bipinnate frond architecture diagnostic of Goeppertella Csee Arrondo and Petriella 1982 for further discussion). Arrondo and Petriella C1982) distinguished species of the genus on the type of `intercalary element' Ci.e. rachial pinnule or lamina). However, other characters can also be used, such as pinnule shape and orientation on the pinna rachis, style of pinnule apex Ci.e. whether acute or obtuse), pinnule size and the type of margins Ci.e. whether entire or undulating). Of the eight species of Goeppertella described prior to Rees C1993a) Csee Arrondo and Petriella 1982 and references therein), G. jeffersonii is most similar to G. frenguelliana, G. microloba, G. macroloba and G. neuqueniana. The style of rachial lamina and pinnule size distinguishes it from G. frenguelliana, which has a greatly reduced lamina, while G. microloba has differently shaped pinnules with undulating margins. G. macroloba has considerably larger pinnules than those of G. jeffersonii, whereas G. neuqueniana pinnules are longer Cwith greater length to width ratios) and have obtuse-rounded apices. Pinnules of G. neuqueniana are also typically separate from one another on the pinna rachis, only becoming con¯uent in apical regions of the pinna. The rachial pinnules of G. microloba, G. macroloba and G. neuqueniana are less pronounced than those of G. jeffersonii, being little more than small lobes in the central regions of the rachial laminae. Morel et al. C1994) assigned two juxtaposed pinna fragments from Botany Bay to Dictyophyllum atuelense. These agree in all respects with G. jeffersonii as described by Rees C1993a), based on more complete material, although their specimens also provide information about sori and sporangia seen on some of the pinnules.

E X P L A N A T I O N O F P L A T E 3 Figs 1±2. Goeppertella jeffersonii Rees. 1, V.63595; fragment near apex of bipinnate frond-member bearing pinnae and rachial pinnules; ´ 3. 2, V.63595; detail of pinnule morphology and venation, with the pinnule on the right showing marginal teeth on its basiscopic margin; ´ 10. Fig. 3. Goeppertella woodii Rees. V.63610; pinna segment; ´ 2. All specimens from Botany Bay.

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Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:03 ALDEN 14 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Goeppertella woodii Rees, 1993a Plate 3, ®gure 3; Plate 4, ®gures 1±2 }1913 Dictyophyllum sp.; Halle, text-®g. 2; pl. 1, ®gs 28, 28a. }1989 Dictyophyllum sp.; Gee, pl. 2, ®g. 13. *}1993a Goeppertella woodii Rees, p. 643, pl. 2, ®gs 1±4; pl. 3, ®gs 1±3, 5; text-®g. 3A. }1994 Dictyophyllum tenuifolium; Morel et al., ®g. 2b, pl. 1, ®g. 2. }1994 Goeppertella neuqueniana Herbst; Morel et al. Cnon Herbst), ®g. 3a. }1994 Goeppertella macroloba Herbst; Morel et al. Cnon Herbst), ®g. 3b, pl. 1, ®g. 4.

Holotype. V.63602; provenance Botany Bay.

Diagnosis Cfrom Rees 1993a). Frond-member bipinnate. Pinnae alternating with rachial lamina; lamina shape irregular, but always broadening from proximal to distal sinus points, occasionally lobed distally. Pinnules wedge-shaped, strongly falcate, relatively narrow in free portions, 6±25 mm long ´ 5±13 mm wide, curving towards pinna apex. Pinnule apices acute to subacute, margins typically entire. Venation reticulate; ®rst order lateral veins arising from main vein, joining with veins arising from rachis between pinnules, dividing to form polygonal vein meshes. Fertile segments with sori typically on rachial lamina and pinnule bases; sori 0´7±1´0 mm across, comprising ten or more sporangia c. 0´1 mm in diameter.

Material. Hope Bay: V.63598, V.63599. Botany Bay: V.63600±V.63619.

Description. For a detailed description of this material, see Rees C1993a, p. 644).

Remarks. G. woodii differs from G. jeffersonii primarily in having an irregular rachial lamina rather than rachial pinnules. G. woodii pinnules are also larger, more falcate and generally narrower than in G. jeffersonii. The rachial lamina of G. woodii is irregular in size and shape, but always broadens from the proximal sinus point to the distal point, and is unlike that in any of other known species of Goeppertella CArrondo and Petriella 1982 and references therein). Of these other species, G. woodii is most similar to G. frenguelliana and G. macroloba. However, the rachial lamina is greatly reduced in G. frenguelliana, being present only as a narrow strip with margins which are parallel to the frond-member rachis, while the lamina in G. macroloba is broadest in its central region, not distally as in G. woodii. The three incomplete pinnules from Hope Bay, assigned by Halle C1913) and Gee C1989) to Dictyophyllum sp., are very similar in shape, size and venation pattern to G. woodii and undoubtedly belong to the same species. Fragmentary specimens from Botany Bay assigned to Dictyophyllum tenuifolium by Morel et al. C1994) agree in all respects with G. woodii, as described by Rees C1993a). Morel et al. C1994) assigned other material from Botany Bay to three species of Goeppertella CG. neuqueniana, G. macroloba and G. herbstii), based, respectively, on one, two and four specimens. In our view, differences between the Botany Bay specimens they assigned to G. neuqueniana and G. macroloba, and G. woodii as described by Rees C1993a) are minor and may be regarded as conspeci®c. The specimens assigned to G. woodii CRees 1993a) and the specimen described by Morel et al. C1994) as G. neuqueniana have little in common with the type material of G. neuqueniana CHerbst 1966, pl. 3, ®g. 22), which has larger and more dissected pinnules. In the type of G. macroloba CHerbst 1964a, ®gs 1±2, 9), the pinnule venation differs from G. woodii, showing distinctly larger vein meshes along the centre of each pinnule around the primary vein, ¯anked by smaller meshes. Also, the rachial lamina is widest in its middle region, not distally as in G. woodii. Goeppertella herbstii differs from the other Hope Bay and Botany Bay species in having longer, narrower pinnules and we agree with this identi®cation of Morel et al. C1994), thus recognising three species of Goeppertella CG. jeffersonii, G. woodii and G. herbstii) in the Botany Bay ¯ora.

Morphogenus HAUSMANNIA Dunker, 1846 Type. Hausmannia dichotoma Dunker emend. Harris, 1961.

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Material. Hope Bay: V.63420, V.63423, and V.63620. Botany Bay: V.63621±V.63623.

Description. For a detailed description of this material, see Rees C1993a, p. 648).

Remarks. Several fragments and one near-complete lamina of Hausmannia have been found at Hope Bay and Botany Bay CRees 1993a). They are similar to H. nariwaensis from Rhaetic ¯oras of Japan COÃ ishi 1932) in their lamina division, marginal lobing, venation pattern and soral details. In contrast to the Japanese specimens, they have a wedge- rather than reniform-shaped lamina Ci.e. the long axis is parallel rather than perpendicular to the median cleft). Although Rees C1993a, p. ?) remarked that `further material is required from these Antarctic localities in order to assess the signi®cance of this difference', he assigned the specimens to H. cf. nariwaensis. Hausmannia deferrariisii Feruglio, 1937 from Argentina and Hausmannia sp. cf. H. deferrariisii from Australia CHerbst 1979) have a reniform lamina which, in addition, is less evenly incised. Prior to Rees C1993a), the only previous record of the genus from Antarctica was from the Albian of Alexander Island CJefferson 1981). The Hope Bay and Botany Bay specimens described by Rees C1993a) are almost identical to some of the Alexander Island material in lamina size, shape and marginal lobing, as well as in venation pattern and soral details CJefferson 1981, pl. 4.12, ®gs 1±2). However, Rees C1993a) considered that the other specimens ®gured by Jefferson C1981, pl. 4.12, ®gs 3±5) differ in the shape of the lamina as well as the marginal lobing and venation, and may possibly be a different species of Hausmannia. Cantrill C1995) has subsequently made a more extensive collection from Alexander Island. This has shown intermediate forms between most of the morphotypes ®gured by Jefferson C1981, pl. 4.12, ®gs 1±4), which should all be assigned to H. papilio Cthe specimen shown by Jefferson in pl. 4.12, ®g. 5 is more probably an angiosperm; Cantrill, pers. comm. 1998). Morel et al. C1994) have described two specimens from Botany Bay as H. papilio, a species ®rst described from the Baquero Formation CLower Cretaceous) in Argentina CFeruglio 1937; Herbst 1960). Rees C1993a) omitted to include H. papilio in his discussion of the Hope Bay and Botany Bay material, considering it to be a suf®ciently distinct species. As Cantrill C1995, p. 250) remarked however, `given the variation observed in leaf morphology . . . it is likely that H. papilio, H. deferrarisi and the Hope Bay fronds are conspeci®c'. Cantrill C1995, p. 250) also stated that `morphologically, H. nariwaensis differs in the uneven dichotomy of the primary venation' from the Alexander Island material, describing the lamina of H. papilio as ranging from reniform to wedge-shaped. Because of this, we agree with Cantrill C1995) and assign the Hope Bay and Botany Bay material to H. papilio, while noting that assignment of specimens to species of Hausmannia is complicated by uncertainties in knowing which characters Ce.g. leaf margin, venation) are important for delimiting them. Studies on the variation in Recent dipteridacean frond morphology might help resolve this issue.

Family MATONIACEAE Presl, 1847 Morphogenus MATONIDIUM Schenk, 1871

Type. Matonidium goeppertii CEttingshausen) Schenk emend. Harris, 1980.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:04 ALDEN 16 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 cf. Matonidium sp.

Text-®gure 2B Material. Botany Bay: D.8965.14B.

Description. Sterile pinna, maximum preserved length 88 mm, central width 19 mm, tapering gradually from centre to base and apex. Rachis up to 0´7 mm wide, tapering distally to 0´3 mm. Pinnules arise at 75±908 then either curve slightly acropetally or remain straight. Pinnules separate, not connected by lamina. Neighbouring pinnule margins closely spaced, often touching. Pinnules opposite to alternate on rachis. Pinnule bases neither expanded nor contracted. Pinnules lanceolate; margins entire and near-parallel for lower 50±80 per cent of length, then converging to apex. Apices typically obtuse, occasionally subacute. Pinnule length 6´5±9 mm, basal width 2´0±2´5 mm. Ratio of pinnule length to basal width 2´9±5´1. Pinnule primary vein strong, 0´1±0´2 mm wide at pinnule base, parallel to margins, persisting nearly to apex. Secondary veins poorly preserved, never seen along full length of pinnule Cup to three basal and apical pairs of secondary veins not preserved). Secondary veins arise at 65±808 from primary vein, reaching margins at 80±908. Secondary veins fork once, angle between forks c. 408, forks parallel for last 50±60 per cent of distance from primary vein to margins. Vein density 40±47 per cm along pinnule margin.

Remarks. Harris C1961) only distinguished Matonidium from Phlebopteris on details of the sori. As this Botany Bay specimen is markedly similar to sterile foliage ®gured as Matonidium goeppertii by Harris C1961) and Appert C1973), it has been tentatively assigned to Matonidium; however, see van Konijnenburg-van Cittert C1993) for an alternative view on this issue. If it were not for its close similarity to Matonidium specimens from other regions, the Botany Bay specimen could be assigned to Cladophlebis. However, it differs from the most similar Cladophlebis species at Hope Bay and Botany Bay CC. oblonga) in having narrower, more closely-spaced pinnules, with a higher secondary vein concentration and secondary veins which reach the pinnule margins at wider angles.

Family DICKSONIACEAE Bower, 1908 Morphogenus CONIOPTERIS Brongniart emend. Harris, 1961

Type. Coniopteris murrayana CBrongniart) Brongniart emend. Harris, 1961

Coniopteris lobata COldham and Morris) Halle, 1913 Plate 5, ®gures 1±2, 4 *1862 Pecopteris C?) CAsplenites) lobata Oldham and Morris, pl. 28, ®g. 1; pls 29±30; pl. 36, ®g. 3. 1877 Pecopteris lobata Oldham and Morris; Feistmantel, pl. 36, ®g. 3. }§1913 Coniopteris? lobata COldham and Morris) Halle, pl. 1, ®g. 27; pl. 3, ®g. 13; text-®g. 5. }p1913 Coniopteris cfr. nephrocarpa Halle, pl. 3, ®gs 11, 11a, 11b. 1988 Pecopteris lobata Oldham and Morris; Sengupta, pl. 13, ®g. 36. }1989 Coniopteris meridionalis Gee, pl. 1, ®gs 10±12.

E X P L A N A T I O N O F P L A T E 4 Figs 1±2. Goeppertella woodii Rees. 1, V.63598, Hope Bay; proximal region of bipinnate frond-member with rachial lamina; ´ 2. 2, V.63619, Botany Bay; partly-fertile pinnae with large broad pinnules, showing sori Cdark spots) in their basal regions; ´ 2. Figs 3±4. Hausmannia papilio Feruglio, Hope Bay. 3, V.63620; near-complete fertile lamina and region of rachis attachment; ´ 1´5. 4, V.63420; fragment of large lamina with pronounced venation, showing vein orders and areas with sori; ´ 5.

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REES and CLEAL, Goeppertella, Hausmannia

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TEXT-FIG. 2. A, Cladophlebis oblonga Halle; D.206.1, frond segment; note that some of the pinnae are distorted; ´ 1. B, cf. Matonidium sp., D.8965.14B; pinna fragment; ´ 1´5. Both specimens from Botany Bay.

Lectotype. Sengupta C1988) stated that Pant and Gujuraja had designated a specimen in the collections of the Geological Survey of India Cnumber GSI 4457) as a neotype of this species. However, this proposal was invalid as it was both unpublished Cit was merely a note accompanying the specimen) and unnecessary Cthree of the six original syntypes are still available). Sengupta refers to GSI 4451 as being the best of these three specimens, as it includes both fertile pinnules and sterile pinnules showing clear venation. We therefore here designate that specimen as the lectotype.

Material. Botany Bay: D.8911.1B, D.8916B, D.8947.4A, D.8947.4B, D.8947.11A, D.8947.17B, and D.8958.10A, D.8958.13B Cpart and c/part). Hope Bay; 8003.

Description. Frond tripinnate, rachis up to at least 2 mm wide, primary pinna rachis 0´5±2´0 mm wide. Primary pinnae 9´0±10´5 mm apart on frond rachis, alternate, arising at c. 408 Cseen in only one specimen, D.8958.10A). Secondary pinna rachis 0´1±0´5 mm wide, typically c. 0´2 mm. Secondary pinnae typically subopposite, occasionally alternate, arising at 35±658, typically c. 50±608. Basalmost secondary pinna arising from basiscopic side of primary pinna rachis.

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Fertile and sterile pinnules similar, occasionally intergrading on the same pinna. Pinnules typically alternate, occasionally subopposite, on secondary pinna rachis. Lowermost pinnule typically arising on acroscopic side of secondary pinna rachis Coccasionally, lowermost pinnules opposite). Pinnules arising at 40±908, typically c. 60±808, from secondary pinna rachis. Neighbouring pinnules 2±3 mm apart Cmeasured between pinnule primary veins). Pinnule length 2±12 mm Ctypically c. 5±8 mm), central width 1´0±2´5 mm Ctypically c. 1´5±2´0 mm). Ratio of pinnule length to central width 2´2±5´3, typically c. 3±4. Pinnule bases constricted symmetrically. Pinnule margins converging gradually Cbeyond basal constriction) towards pinnule apex, apex comprising a single lobe. Pinnule margins usually lobed, from c. 50±75 per cent of distance from lobe apex to pinnule primary vein, but never lobed to primary vein Cmargins becoming crenulate and then entire towards secondary pinna apex). Pinnules typically have 7±13 lobes C3±6 lobes per margin, with a single lobe at pinnule apex). Fertile pinnule lobes typically c. 0´3±0´9 mm long and c. 0´3±0´5 mm wide at their base. Sterile pinnule lobes typically c. 0´4±0´7 mm long and c. 0´3±0´5 mm wide at their base. Lobe margins entire. Apices of fertile pinnule lobes obtuse; apices of sterile pinnule lobes typically obtuse, occasionally acute, directed towards pinnule apex. Apical lobe typically having same dimensions as marginal lobes of the same pinnule, occasionally larger or smaller. Fertile pinnule lobes with thick reniform `bulges' Csori) along their margins; sori typically c. 0´2 mm wide Ci.e. about one-third of total lobe length). There is typically one sorus per lobe, but in the basal region of the pinnule there may be up to three sori per lobe. Pinnule primary vein typically straight, occasionally slightly sinuous, persisting nearly to pinnule apex. Secondary veins arise at 55±658 from primary vein; secondary veins typically simple, one vein entering each lobe, persisting to base of sorus in fertile pinnules, persisting almost to lobe apex in sterile pinnules. Secondary veins occasionally once forking in sterile pinnule lobes, between c. 60±80 per cent of distance from primary vein to lobe apex. Rarely, secondary veins fork twice in lowermost lobes of sterile pinnules, once in those of fertile pinnules.

Remarks. Halle C1913) compared sterile frond fragments from Hope Bay with specimens that had been described from India as Pecopteris lobata Ce.g. Feistmantel 1877). However, the associated fertile material was thought by him to differ signi®cantly from the fertile material associated with the Indian P. lobata, so he assigned it to Coniopteris cfr. nephrocarpa. Gee C1989) described Hope Bay specimens showing both fertile and sterile pinnules on the same pinna, thus con®rming that they are conspeci®c. She found it dif®cult to compare these with the Indian Pecopteris lobata because the latter was poorly illustrated, particularly the sori. However, specimens from Onthea CIndia) examined by Gee C1989) seemed to show pinnules with bidentate lobes, and with the distalmost lobe of each pinnule being larger than the others on the pinnule. According to Gee, the Hope Bay pinnule lobes were never incised and the distalmost lobe was never larger than the others. Consequently, Gee assigned the Hope Bay material to a new species, C. meridionalis. The new material from Botany Bay shows that, although the apical lobe is typically similar or slightly smaller in size compared with marginal lobes on the same pinnule, they are occasionally larger. Furthermore, a specimen of P. lobata from its type region CRajmahal Hills) described by Sengupta C1988) shows the pinnule lobes to be entire, and it generally compares closely with the Hope Bay material. There seems little justi®cation, therefore, for taxonomically distinguishing the Antarctic and Indian material, which we refer to as Coniopteris lobata, especially in view of the occurrence of fertile and sterile pinnules on the same pinna CGee 1989, and this study).

Coniopteris cf. murrayana CBrongniart) Brongniart emend. Harris, 1961 Plate 5, ®gures 3, 5 p}1913 Coniopteris hymenophylloides CBrongniart) Seward; Halle, pl. 3, ®gs 27, 28, 28a. }1989 Coniopteris murrayana CBrongniart) Brongniart; Gee, pl. 1, ®g. 9.

Material. Hope Bay: D.37.1a, D.37.1e Cpart and counterpart).

Description. Partly fertile bipinnate leaf, known from one primary pinna fragment. Primary pinna 108 mm long, rachis up to 1´4 mm wide, secondary pinna rachis up to 0´7 mm wide. Secondary pinnae 45±52 mm long, alternate on primary pinna rachis, arising at 40±658. Neighbouring secondary pinnae 9±17´5 mm apart on primary pinna rachis. Pinnules partly fertile, lobed; typically, one sorus at the apex of each lowermost acroscopic lobe Crarely, on the two lower

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acroscopic lobes). Pinnules arise at 35±508 on secondary pinna rachis, typically alternate, occasionally opposite. Pinnule bases decurrent basiscopically, contracted acroscopically; pinnules contracted symmetrically above level of basiscopic decurrency. Neighbouring pinnules 4´5±5´5 mm apart, lowermost pinnule arising from acroscopic side of secondary pinna rachis. Pinnule length 4´5±14´5 mm, lobe length Cmeasured from pinnule primary vein) 4±7 mm. Free length of lobe 0´8±3´7 mm, basal width 0´7±1´4 mm. Lobe apices typically subacute, occasionally either acute or obtuse. Venation indistinct; primary vein persisting to pinnule apex, secondary veins arising at 10±208, one secondary vein per lobe. Secondary vein typically persisting to lobe apex; secondary vein occasionally bifurcating within a lobe, the two subsequent veins persisting to either side of lobe apex. In fertile lobes, secondary vein persists to base of terminal sorus. Sori round or ovoid, seen as depressions Cprotrusions on specimen counterpart) in the lobe lamina. Soral length 0´6±0´9 mm, maximum Cˆ central) width 0´6±1´0 mm. Ratio of soral length to maximum width 0´6±1´5. Fine details of sori not preserved.

Remarks. The specimen from Hope Bay is similar to Yorkshire material illustrated as Coniopteris murrayana by Harris C1961). In particular, a partly-fertile specimen illustrated by Harris C1961, ®g. 56E±F) is closely similar, except that the sori are located at the apices of both the acroscopic and basiscopic lobes Cthey are only on the acroscopic lobes in the Hope Bay specimen; Pl. 5, ®g. 5). According to Harris C1961), the lowermost pinnules of C. murrayana are catadromic Ci.e. arise basiscopically), whereas in the Hope Bay specimen it is acroscopic. However, until further material is found at Hope Bay, it is best referred to as Coniopteris cf. murrayana.

Coniopteris sp. A Plate 8, ®gure 1 p}1913 Coniopteris hymenophylloides CBrongniart) Seward; Halle, pl. 3, ®g. 29.

Material. Botany Bay: D.8954.3B, R.1310.83.

Description. Fertile leaf, known from two pinna fragments. Pinna rachis 1´1mm wide, basal width of secondary branches 0´3±0´5 mm. Secondary branches alternate on pinna rachis, arising at 50±758, from 6±7 mm apart and 22´5±30´0 mm long. Tertiary branches typically alternate, occasionally opposite, on secondary branch, arising at 35±558. Bases of tertiary branches slightly decurrent or straight basiscopically, and slightly constricted or straight acroscopically on secondary branch. Tertiary branches 1´5±2´0 mm apart, lowermost tertiary branch arising from basiscopic side of secondary branch. Margins of tertiary branches typically entire, lowermost branches segmented Cup to three segments per tertiary branch). Segments sterile, arising at 15±508, segment apices acute or subacute. Margins of typical Cˆ non-basal) tertiary branches diverging from base to apex; each tertiary branch capped by one sorus. Tertiary branches typically c. 3 mm long Cexcluding sorus), and 0´3±0´5 mm wide at their bases. Ratio of tertiary branch length to basal width ranging from 8±15. One vein present in each tertiary branch, persisting to base of sorus. Sori hemispherical, straight along their bases, narrowing gradually to obtuse, rounded apices. Soral bases inserted at c. 908 to tertiary branch axis. Length of sori 1´0±1´1 mm, maximum Cˆ basal) width 1´0±1´9 mm. Ratio of soral length to maximum width 0´5±1´1. Sori coali®ed, lacking ®ne details.

Remarks. Coniopteris sp. A is included in the discussion of Coniopteris sp. B, below.

E X P L A N A T I O N O F P L A T E 5 Figs 1, 2, 4. Coniopteris lobata COldham and Morris) Halle. 1, 8003, Hope Bay; frond segment bearing alternate secondary pinnae and broad rachises; ´ 1. 2, 4, Botany Bay. 2, D.8947.17B; fertile secondary pinnae attached to primary pinna rachis; ´ 1´5. 4, D.8947.17B; detail showing reniform sori on pinnule lobes; ´ 5. Figs 3, 5. Coniopteris cf. murrayana CBrongniart) Brongniart, D37.1A, Hope Bay; part of frond shown in Plate 2, ®gure 1. 3, partly fertile frond fragment; ´ 1. 5, detail showing sori at apices of ultimate segments; ´ 4.

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REES and CLEAL, Coniopteris

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:04 ALDEN 22 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Coniopteris sp. B Plate 8, ®gure 2 p}1913 Coniopteris hymenophylloides CBrongniart) Seward; Halle, pl. 3, ®gs 24, 24a. }1989 Coniopteris hymenophylloides CBrongniart) Seward; Gee, pl. 1, ®gs 7±8.

Material. Hope Bay: 5622B.

Description. Fertile leaf, known from one pinna fragment. Pinna rachis 1 mm wide, basal width of secondary branches 0´8±0´9 mm. Secondary branches alternate on pinna rachis, arising at 40±608, 9´0- 9´5 mm apart and 10±16 mm long. Tertiary branches alternate on secondary branch, arising at 40±708. Bases of tertiary branches decurrent basiscopi- cally, straight acroscopically. Tertiary branches 3±4 mm apart. Lowermost tertiary branch typically arising from acroscopic Coccasionally basiscopic) side of secondary branch. Margins of tertiary branches entire, diverging from base to apex; each tertiary branch capped by one sorus. Tertiary branches 1´5±2´0 mm long Cexcluding sorus), and 0´4±0´7 mm wide at their base. Ratio of tertiary branch length to basal width 2´1±4´2. Venation not preserved. Sori hemispherical, straight along their bases, narrowing to obtuse, rounded apices. Soral bases inserted at 30±908 to tertiary branch axis. Sori 1´0±1´6 mm long and of maximum Cˆ basal) width 2´0±2´6 mm. Ratio of soral length to maximum width 0´4±0´7. Fine details of sori not preserved.

Remarks. Three fertile pinna fragments from Hope Bay and Botany Bay are assigned here to two species, Coniopteris sp. A and Coniopteris sp. B. Fertile tertiary branches of C. sp. A are longer and narrower than those of C. sp. B, and are more closely spaced on the secondary branch. The size, shape, and insertion style of the sori also serves to distinguish the two species. We also include here Hope Bay specimens assigned to C. hymenophylloides by Halle C1913) and Gee C1989). The Hope Bay and Botany Bay specimens show some comparison with C. hymenophylloides and C. simplex from the Middle Jurassic of Yorkshire CHarris 1961). However, the longer and narrower tertiary branches of C. sp. A and C. sp. B distinguish them from some specimens of C. hymenophylloides, and the sorus in other specimens of C. hymenophylloides is attached to the acroscopic margin of the tertiary branch. Fertile pinnae of C. simplex Ce.g. Harris 1961, p. 143, ®gs C, F, I) resemble closely C. sp. A and C. sp. B, in lobe length and width, as well as soral size and shape.

Order OSMUNDALES Family OSMUNDACEAE Berchtold and Presl, 1820 Morphogenus TODITES Seward emend. Harris, 1961

Type. Todites williamsonii CBrongniart) Seward emend. Harris, 1961.

Todites williamsonii CBrongniart) Seward emend. Harris, 1961

Plate 6, ®gures 1, 3, 5; Text-®gure 3A±B 1828 Pecopteris Williamsonis Brongniart, p. 57 Cname only). 1829 Pecopteris Williamsonis Brongniart; Phillips, pl. 10, ®g. 7 Cpoor, sterile fragment). *1834 Pecopteris Williamsonis Brongniart, p. 324, pl. 110, ®gs 1±2. §1900 Todites williamsoni CBrongniart) Seward, p. 87, pl. 14, ®gs 2, 5, 7; pl. 15, ®gs 1±3; pl. 21, ®g. 6; text-®g. 12.

TEXT-FIG. 3. A±B, Todites williamsonii CBrongniart) Seward. A, D.8941.7A; B, D.8865.1A. C, Cladophlebis antarctica Halle, D.8944.22A. D, Cladophlebis denticulata CBrongniart) Fontaine, D.8936.3A. E±F, Cladophlebis oblonga Halle, D.9042. E, pinna segment; F, close-up of pinnule. Upper scale bar refers to A±E, lower scale bar to F. All specimens from Botany Bay.

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}1913 Todites Williamsoni CBrongniart) Seward; Halle, pl. 3, ®gs 1±5; pl. 8, ®g. 1b. }1913 Cladophlebis CConiopteris?) arguta CLindley and Hutton) Seward; Halle Cnon Lindley and Hutton), pl. 2, ®gs 1±3, 5. 1956 Todites Williamsoni CBrongniart) Seward; MeneÂndez, pl. 3, ®gs 4±7. 1961 Todites williamsoni CBrongniart) Seward; Harris, p. 87. }1989 Todites grahamii CBrongniart) Seward; Gee, pl. 2, ®gs 17±19; pl. 3, ®gs 21±22; text-®g. 2. See Harris C1961) for other synonyms.

Holotype. Specimen ®gured by Brongniart C1834, pl. 110, ®gs 3±4); provenance Yorkshire Jurassic. Present location of this specimen unknown.

Material. Botany Bay: D.8865.1A, D.8865.2A, D.8877.1B, D.8877.2B, D.8912.1B, D.8941.7A, D.8958.28B, D.8958.29A, D.8958.30A, D.8958.31B, D.89582.5A, D.8965.32A. CSterile fronds and pinnae, except D.8965.32A; fertile).

Description. Large bipinnate frond, up to 340 mm long and 270 mm wide, complete extent unknown. Sterile frond rachis up to 7 mm wide, fertile up to 8´5 mm wide. Fronds either sterile or fertile. Sterile pinnae alternate to subopposite on rachis, 10±15mm apart, arising at 55±808. Sterile pinna rachis 0´8±1´2 mm wide. Pinnules arising at 55±908 from sterile pinna rachis, lowermost pinnule arising on basiscopic side. Pinnules separate, typically alternate but occasionally opposite on rachis. Acroscopic base of pinnule typically expanded, occasionally straight or slightly contracted, basiscopic base straight or slightly contracted. Pinnule margins typically entire Coccasionally, slightly undulating). Pinnule apices acute or subobtuse. Pinnule margins near parallel to c. 50±70 per cent of distance from base to apex, then converging to apex. Pinnules cuneate or falcate. Pinnule length ranging from 3´5 to 14´5 mm Ctypically 7±12 mm), basal width 1´0±6´5 mm Ctypically 3±5 mm). Ratio of pinnule length to basal width c. 2±5 Ctypically 2±3). Pinnule primary vein straight or slightly sinuous, narrowing gradually and persisting to c. 50±70 per cent of distance from base to apex, then indistinguishable in width from secondary veins. Secondary veins arising at narrow angles from primary vein, reaching margins at c. 40±508 in lower and central regions of pinnule, this angle decreasing steadily towards pinnule apex. Lowermost secondary vein typically arising on basiscopic side of pinnule, occasionally on acroscopic side. Secondary veins usually forking twice in central region of pinnule, lowermost secondary veins may fork three times. Secondary veins in apical region of pinnule typically forking once, veins becoming simple at pinnule apex. Vein density at pinnule margin Cin central region of pinnule) 16±50 per cm, typically 20±25 per cm C40±50 per cm in smaller pinnules). Fertile pinnae 12´5 mm apart on frond rachis, arising at c. 65 8 Cseen on one specimen, Pl. 6, ®g. 1); pinna rachis up to 1 mm wide. Fertile pinnules arising at 85±958 from pinna rachis, lowermost pinnule arising on basiscopic side. Pinnules separate, alternate to opposite on rachis, acroscopic base expanded, basiscopic straight or occasionally slightly contracted. Pinnule margins typically entire Coccasionally slightly undulating). Pinnule apices ranging from obtuse Crounded) to acute. Pinnules oblong to falcate, 5±6 mm long, basal width from 2´5±3 mm. Ratio of pinnule length to basal width c. 2±3. Pinnules commonly either covered in small, round, densely packed sporangia, or with a sporangia-free zone along the pinnule margins. Other pinnules have variable sporangia cover, giving varying degrees of vein exposure. Venation pattern, where seen on partly fertile pinnules, the same as in sterile pinnules. Lowermost vein typically arising on basiscopic side of pinnule, occasionally on acroscopic side. Vein density on margins in central region of fertile pinnules 25±30 per cm.

Remarks. There has been considerable confusion in the literature regarding Todites williamsonii, T. grahamii, Cladophlebis grahamii and C. denticulata from Hope Bay and Argentina. Todites william- sonii was identi®ed in the Hope Bay ¯ora by Halle C1913). Frenguelli C1947) erected C. grahamii for other material from Hope Bay that Halle C1913) had identi®ed as C. denticulata, as well as for new material from NeuqueÂn, Argentina. Gee C1989) believed the fertile specimens of T. williamsonii from Hope Bay to represent fertile C. grahamii, and accordingly combined the Hope Bay material of T. williamsonii Cboth fertile and sterile) with C. grahamii, as Todites grahamii. However, Frenguelli C1947) clearly considered C. grahamii to be closest to C. denticulata and no comparison was made with T. williamsonii. His plates of C. grahamii show specimens from Argentina with clear Cl. denticulata-like pinnule morphology and venation, and there is no similarity between them and the specimens of T. williamsonii from Hope Bay and Botany Bay.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:05 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 25 Thus, the material from Hope Bay that Gee C1989) assigned to Todites grahamii should be reassigned to Todites williamsonii. The assignment to T. williamsonii is further strengthened by the study of new material, including partly fertile pinnules, from both Hope Bay and Botany Bay. The speci®c epithet grahamii should only be used in combination with Cladophlebis, since it is only known at present from sterile Argentine material. The position of C. grahamii with respect to the material from Hope Bay and Botany Bay assigned here to C. denticulata is discussed below.

Family unknown Morphogenus CLADOPHLEBIS Brongniart, 1849

Type. Cladophlebis albertsii CDunker) Brongniart, 1849

Remarks. Text-®gure 3 shows examples of the pinnules of Cladophlebis from Hope Bay and Botany Bay, together with sterile foliage of Todites williamsonii. The following key allows the identi®cation of these species.

1. a. Pinnule margins entire ...... 2 b. Pinnule margins serrate ...... 3 2. a. Pinnule primary vein persisting to at least 90 per cent of distance from base to apex. Secondary veins in central region of pinnule once-forking, parallel, arising at wide angles to primary vein...... Cladophlebis oblonga b. Pinnule primary vein persisting only to between 50±70 per cent of distance from base to apex, then indistinguishable from secondary veins. Secondary veins in central region of pinnule variably-forking, divergent, arising at narrow angles to primary vein ...... Todites williamsonii 3. a. Ratio of pinnule length to basal width typically > 3, up to 4. Secondary vein concentration at margin Cin central region of pinnule) typically < 18 per cm ...... Cladophlebis antarctica b. Ratio of pinnule length to basal width typically 1´5 to < 3. Secondary vein concentration at margin Cin central region of pinnule) typically > 18 per cm ...... Cladophlebis denticulata

Cladophlebis antarctica Halle, 1913

Plate 6, ®gure 2; Plate 7, ®gure 3; Text-®gure 3C *}1913 Cladophlebis antarctica Halle, pl. 1, ®gs 15±23, 24?; pl. 3, ®g. 6. }1947 Cladophlebis antarctica Halle; Frenguelli, text-®g. 5a±d Cre-®guring of Hope Bay material). cf.1963 Cladophlebis cfr. antarctica Halle; Bonetti, pl. 1, ®g. 2. 1964b Cladophlebis antarctica Halle; Herbst, pl. 1, ®g. 8; pl. 2, ®g. 16. cf.1981 cfA Cladophlebis antarctica Halle; Jefferson, pl. 4.5, ®gs 1±2. }1989 Cladophlebis antarctica Halle; Gee, pl. 2, ®g. 15; pl. 3, ®g. 24. See Gee C1989) for other synonyms and closely similar specimens.

Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20030 CHalle 1913, pl. 1, ®g. 21). Designated by Gee C1989).

Material. Hope Bay: D.21.9. Botany Bay: D.8876A, D.8905.2B, D.8906.5B, D.8906.6B, D.8914.13B, D.8915A, B, D.8941.5A, B, D.8941.6B, D.8944.2A, D.8944.22A, D.8947.3B, D.8953.18A, D.8972.1B Cin part), D.8972.2A, B, D.9005.2A.

Description. Sterile frond fragments, frond rachis up to 4´5 mm wide, pinna rachis up to 2 mm wide. Pinnae 5´5±14´5 mm apart on frond rachis, inserted at c. 40±708. Pinnules arising at 35±768, typically c. 50±708, on pinna rachis, lowermost pinnule arising on basiscopic side. Pinnules typically connected by lamina c. 0´5±1´5 mm long, occasionally separate, alternate to subopposite on rachis. Pinnule base typically slightly expanded or straight acroscopically and slightly contracted or straight basiscopically. Pinnule margins typically entire to 50±70 per cent of distance from base to apex, then serrate to apex. Pinnules narrowly cuneate or falcate, margins near-parallel in ®rst 60±80 per cent of distance from base to apex, then converging to acute apex. Pinnule length 5´5±35 mm, typically 10±20 mm, basal width 2´5±7´5 mm, typically 3±5 mm. Ratio of pinnule length to basal width 2´9- 4´7, typically 3±4.

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Pinnule primary vein straight, persisting nearly to apex then forking symmetrically, one vein to each margin. Secondary veins reaching margins at 40±468 in central region of pinnule. Lowermost secondary vein typically arising on basiscopic side of pinnule, lowermost veins occasionally opposite. Secondary veins typically forking once, forks parallel, lowermost veins occasionally forking twice. Secondary veins forking in ®rst third of distance from primary vein to pinnule margins Cthe ultimate two or three pairs of veins at pinnule apex are simple, unforked). Secondary vein concentration at margins Cin central region of pinnule) 10±20 per cm, typically c. 10±16 per cm. Interval between secondary veins at margins Cin central region of pinnule) c. 0´5±1´0 mm. Remarks. Halle C1913) erected Cladophlebis antarctica for specimens from Hope Bay. He considered them closely similar to C. denticulata, but distinguished the former as having a narrower frond rachis, wider angle of pinna attachment to the frond rachis, more elongate pinnules and more serrate pinnule margins. In our view, however, these criteria are unreliable: wide C. denticulata-type frond rachises have been observed bearing C. antarctica-like pinnules; there is a signi®cant overlap in the angle of pinna attachment between the two morphotypes; and the apparent degree of pinnule serration is highly variable and can be strongly in¯uenced by taphonomy Csigni®cantly, specimens assigned by Harris 1961 to C. denticulata have a very similar serration pattern to the Hope Bay and Botany Bay specimens that have been described as C. antarctica). Gee C1989) also distinguished C. antarctica by its opposite to subopposite pinnae Calternate in C. denticulata), the angle of pinnule attachment C908 at the pinna base, decreasing to 508 in C. antarctica; it varies from 40±908 in C. denticulata, regardless of pinnule position on the pinna rachis), its more acute pinnule apices and the more widely spaced secondary veins. However, the specimens ®gured as C. denticulata by Harris C1961) show a combination of all these features and clearly do not provide a reliable means of distinguishing it from C. antarctica. Clearly, no single character can be used to distinguish the two species reliably. If they are to be regarded as taxonomic synonyms, an emended diagnosis will be needed for C. denticulata Cthe senior name). We are reluctant to do this here as we only have available relatively poorly preserved specimens. Since it is possible to assign most specimens to either the C. denticulata or C. antarctica morphotypes, we have provisionally maintained them as distinct species. However, it is clear that the differences between them are far less marked than was believed by Halle C1913) and Gee C1989).

Cladophlebis denticulata CBrongniart) Fontaine emend. Harris, 1961

Plate 6, ®gure 4; Plate 7, ®gures 1±2; Text-®gure 3D *1834 Pecopteris denticulata Brongniart, p. 301, pl. 98, ®gs 1±2. §1889 Cladophlebis denticulata CBrongniart) Fontaine, p. 71. }1913 Cladophlebis denticulata CBrongniart) Fontaine; Halle, pl. 2, ®gs 7±9; text-®g. 3. p}1947 Cladophlebis Grahami Frenguelli, text-®g. 7 Cre-®guring of Hope Bay material); non text-®g. 1b; pl. 3, ®gs 1±7; pl. 4, ®gs 1±3 Ctypes of C. grahamii). 1956 Cladophlebis denticulata CBrongniart) Fontaine; MeneÂndez, pl. 2, ®g. 3. 1963 Cladophlebis denticulata CBrongniart) Fontaine; Bonetti, pl. 1, ®gs 1, 5. 1971 Cladophlebis denticulata CBrongniart) Fontaine; Herbst, ®g. 9. cf. 1976 Cladophlebis matsumotoi Kimura, text ®g. 7. }1989 Cladophlebis denticulata CBrongniart) Fontaine; Gee, pl. 2, ®g. 14; pl. 3, ®g. 25. See Harris C1961) for other synonyms.

E X P L A N A T I O N O F P L A T E 6 Figs 1, 3, 5. Todites williamsonii CBrongniart) Seward, Botany Bay. 1, D.8965.32A; fertile frond segment; ´ 1. 3, D.8965.32A; detail showing sporangia on fertile pinnules; ´ 2´5. 5, D.8941.7A; sterile fragment showing venation; ´ 3. Fig. 2. Cladophlebis antarctica Halle, D.8941.6B, Botany Bay; frond segment; ´ 1. Fig. 4. Cladophlebis denticulata CBrongniart) Fontaine, D.39.16, Hope Bay; frond fragment showing damaged as well as typical pinnules; ´ 0´75.

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REES and CLEAL, Chadophlebis, Todites

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Holotype. Specimen ®gured by Brongniart C1834); current location unknown.

Material. Hope Bay: D.37.26, D.39.13B, D.39.16. Botany Bay: D.8914.7A, D.8914.9A, D.8914.11A, D.8914.14A, D.8934B, D.8936.3A, D.8938.7B, D.8953.1B, D.8953.2A, D.8972.1 Cin part).

Description. Sterile frond fragments. Frond rachis is up to 6 mm wide, pinna rachis up to 2 mm wide. Pinnae typically alternate, occasionally subopposite, 11±30 mm Ctypically c. 14±20 mm) apart on frond rachis, arising at c. 358. Pinnules arise at 35±858 Ctypically 55±708) on pinna rachis, lowermost pinnule arising on basiscopic side. Pinnules typically connected by lamina c. 0´5±1´0 mm long Coccasionally separate), typically alternate on pinna rachis, occasionally subopposite or opposite. Pinnule base expanded acroscopically, and slightly expanded, straight, or slightly contracted basiscopically. Pinnule margins typically entire to 50±70 per cent of distance from base to apex, then ®nely serrate to apex. Pinnules cuneate, falcate, margins converging from pinnule base to acute apex. Pinnules 5´5±19´5 mm long Ctypically 6±17 mm), with a basal width 2´5±7´5 mm Ctypically 3±6 mm). Ratio of pinnule length to basal width 1´4 to 3´7, typically c. 1´5 to < 3. Pinnule primary vein straight, persisting nearly to apex, then forking symmetrically, one vein to each margin. Secondary veins reaching margins at 30±558 in central region of pinnule. Lowermost secondary vein arising on basiscopic side of pinnule. Secondary veins typically forking once, lowermost basiscopic vein often forking twice. Secondary veins forking in ®rst one-third of distance from primary vein to pinnule margins. Secondary veins in apical region of pinnule remain unforked. Vein density in central region of pinnule 16±35 per cm along margin Ctypically 18±25 per cm). Interval between secondary veins at margins Cin central region of pinnule) c. 0´4±0´5 mm. Well- preserved pinnules often show closely spaced pits or protrusions Cdiameter c. 30 mm) on their surfaces.

Remarks. When Frenguelli C1947) erected Cladophlebis grahamii, he included Hope Bay material assigned by Halle C1913) to C. denticulata Csee preceding discussion of T. williamsonii). Although he named the species after the provenance of the Hope Bay material CGraham Land), Frenguelli's description was based clearly on the Argentine specimens, from Paso Flores and Piedra Pintada in NeuqueÂn Province, and Herbst C1971) has designated one of them as the lectotype. These Argentine specimens have signi®cantly smaller pinnules C< 10 mm long) than typical C. denticulata, such as ®gured by Harris C1961). As they are attached to a relatively wide rachis C1´5±2´0 mm wide), their small size is unlikely to have been due to them coming from the apical region of a frond. On present evidence, it seems more correct to retain the name C. grahamii for this Argentine material, while returning the Hope Bay material to C. denticulata. As pointed out by Schweitzer et al. C1997), at least two types of fern had sterile leaves of the C. denticulata type: Todites and Osmundopsis. They argued that those of the Todites-type tended to have larger pinnules C25±25 mm long, as opposed to 15±20 mm long in Osmundopsis) although there were intermediate forms, which made the distinction dif®cult. It is noteworthy that the Botany Bay specimens of Todites williamsonii has pinnules that are 3´5±14´5 mm long, which is smaller than those of Osmundopsis quoted by Schweitzer et al. C1997).

Cladophlebis oblonga Halle, emend. nov.

Text-®gures 2A, 3E±F *}1913 Cladophlebis oblonga Halle, p. 13, pl. 2, ®g. 6; text-®g. 4. ?p}1947 Cladophlebis Grahami Frenguelli, text-®g.1b Cre-®guring of Hope Bay material). 1980 Cladophlebis oblonga Halle; Arrondo and Petriella, pl. 3, ®g. a.

E X P L A N A T I O N O F P L A T E 7 Figs 1±2. Cladophlebis denticulata CBrongniart) Fontaine. 1, D.39.13B, Hope Bay; frond fragment bearing typical pinnules; ´ 1. 2, D.8936.3A, Botany Bay; pinna segment showing typical pinnule margins and venation; ´ 2. Fig. 3. Cladophlebis antarctica Halle, D.8941.5A, Botany Bay; pinna segment showing typical toothed pinnule margins and venation; ´ 1´5.

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REES and CLEAL, Cladophlebis

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1981 cfA Cladophlebis oblonga Halle; Jefferson, pl. 4.3, ®gs 1±6. 1986 Cladophlebis sp. cf. C. oblonga Halle; Drinnan and Chambers, ®gs 18A, 19C. }1989 Cladophlebis oblonga Halle; Gee, pl. 2, ®g. 16; pl. 3, ®g. 23. See Gee C1989) for other synonyms.

Emended diagnosis. Fronds with typically opposite or subopposite pinnae, becoming alternate towards apex, arising at about 60±758, decreasing to 45±508 near frond apex, 13±19 mm apart and up to at least 60 mm long. Lowermost pinnule arising on basiscopic side of pinna rachis, pinnules arising at c. 55±908, typically c. 758, pinnule margins entire, pinnules typically oblong with obtuse apices, occasionally falcate with acute apices. Pinnule length generally 2±3 times basal width. Primary vein persisting almost to pinnule apex, secondary veins typically fork once, lowermost ones occasionally fork twice, reaching margins at about 50±708, near-parallel to each other, decreasing towards pinnule apex. Vein concentration in central region of pinnule 20±40 per cm along the margin, typically 25±30 per cm.

Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20024 CHalle 1913, text-®g. 4; pl. 2, ®g. 6; Gee 1989, pl. 2, ®g. 16; pl. 3, ®g. 23). Designated by Gee C1989).

Material. Botany Bay: D.8911.5A, D.8911.6B, D.9007.1A, D.9007.2B, D.9007.4A, D.9042, D.206.1.

Description. Sterile fronds; maximum preserved frond rachis width 1´5 mm, pinna rachis up to 1 mm wide. Pinnae typically opposite or subopposite on frond rachis, becoming alternate towards frond apex. Pinnae arising at 60±758, decreasing to 45±508 near frond apex, 13±19 mm apart on frond rachis. Pinnae up to 60 mm long Capices not preserved). Pinnules arising at 55±908, typically 70±758, on pinna rachis, lowermost pinnule arising on basiscopic side. Pinnules typically connected by lamina c. 0´3±0´5 mm long Coccasionally separate), typically alternate on pinna rachis, occasionally subopposite or opposite. Pinnule base expanded acroscopically, or straight Ci.e. acroscopic and basiscopic margins parallel). Pinnule margins entire. Pinnules typically oblong with obtuse apices, margins near-parallel to between c. 80±90 per cent of distance from base to apex, then converging to apex. Pinnules occasionally oblong or falcate on same pinna, with obtuse or acute apices. Pinnule length 5´5±10´5 mm, typically 6´0±8´5 mm, basal width 2´0±4´0 mm, typically 2´5±3´0 mm. Ratio of pinnule length to basal width ranging from 2±3´5, typically 2±3. Pinnule primary vein straight, persisting almost to apex then forking symmetrically, one vein to each margin. Secondary veins reach margins at c. 50±708 in basal and central regions of pinnule, decreasing to c. 408 near pinnule apex. Lowermost secondary vein arising on basiscopic side of pinnule. Secondary veins typically forking once in ®rst third of the distance from primary vein to pinnule margins in basal region of pinnule, gradually forking further from primary vein, towards pinnule apex. Lowermost secondary veins occasionally forking twice. Secondary veins in apical region of pinnule Ccommonly the distalmost two or three pairs of veins in the pinnule) remaining simple, unforked. Vein density in central region of pinnule 20±40 per cm along margin, typically 25±30 per cm.

Remarks. This species has been accepted by Frenguelli C1947), Herbst C1971) and Gee C1989). The new material described here provides additional details of the frond and primary pinnae.

Morphogenus SPHENOPTERIS CBrongniart) Sternberg, 1825 Type. Sphenopteris elegans CBrongniart) Sternberg, 1825

Sphenopteris nordenskjoeldii Halle, emend. nov. Plate 8, ®gure 3 *}1913 Sphenopteris NordenskjoÈldii Halle, pl. 3, ®gs 7±8. 1963 Sphenopteris NordenskjoÈldii Halle; Bonetti, pl. 6, ®gs 1±2. }1989 Sphenopteris nordenskjoeldii Halle; Gee, pl. 4, ®g. 31.

Emended diagnosis. Frond segments at least bipinnate, bearing highly dissected pinnae and pinnules with thin lamina and pronounced venation, appearing dichotomous. Pinnules deeply lobed, apices obtuse.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:05 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 31 Primary veins persisting to pinnule apices, one secondary vein entering each primary lobe then forking into secondary lobes, persisting to lobe apices. Fertile pinnules bearing sori at lobe apices, one sorus per lobe

Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20048 CHalle 1913, pl. 3, ®g. 8; Gee 1989, pl. 4, ®g. 31). Designated by Gee C1989).

Material. Hope Bay: V.63421.

Description. Partly fertile primary pinna fragment with thin, highly dissected pinnules. Complete frond not known, but at least bipinnate. Primary pinna rachis up to 1´8 mm wide, comprising a thick central strand Cup to 0´8 mm wide), winged on either side with a thin lamina. Secondary pinna rachis similar to that of primary pinna, 1´1±1´3 mm wide Ccentral strand 0´4±0´5 mm wide). Secondary pinnae 13´5±15 mm apart on primary pinna rachis, alternate, arising at 30±358. Pinnules 4±7 mm apart on secondary pinna rachis, alternate, arising at 20±458. Lowermost pinnule arising from acroscopic side of secondary pinna rachis. Pinnules 13´0±20´5 mm long, up to 7 mm wide. Pinnule margins deeply lobed, lobe apices obtuse. Pinnule lamina thin, surrounding primary and secondary veins. Primary vein 0´1±0´2 mm wide at pinnule base. Venation distinct; primary vein persisting to pinnule apex, secondary veins alternate, one secondary vein entering each primary lobe then forking into secondary lobes, persisting to lobe apices. Primary lobes alternate on pinnule, arising at 25±358. Lowermost primary lobe arising either from basiscopic or acroscopic side of pinnule primary vein. Primary lobes 2´5±4´0 mm apart on pinnule primary vein Cmeasured between pinnule secondary veins). Primary lobe Cfrom pinnule primary vein) 5±7 mm long. Free length of primary lobe 4±7 mm, basal width 0´8±0´9 mm. Primary lobes free for c. 80±100 per cent of their length. Secondary lobe 2´9±3´3 mm long Cmeasured from where pinnule secondary vein dichotomises), free length of secondary lobe 1´9±2´2 mm; secondary lobes free for c. 65±70 per cent of their length. Pinnules typically sterile. Occasionally, however, a single sorus is visible as an apparent swelling of the vein in the lobe apex. Sori varying from 0´8 ´ 0´4 mm to 0´5 ´ 0´5 mm; ratio of soral length to width 0´8±2.

Remarks. This species is represented in the new material by one partly fertile specimen from Hope Bay. It differs from any other species in the Hope Bay and Botany Bay ¯oras by its pinnules having a thin lamina, deeply incised lobes, and a dichotomous venation. The new specimen is the ®rst fertile example of this species to be found. Gee C1989) compared S. nordenskjoeldii with Sphenopteris metzgerioides Harris from the Middle Jurassic of Yorkshire and Kachchh, India CHarris 1961; Bose and Banerji 1984), which is known only from sterile fragments. The Yorkshire specimens have generally longer and narrower pinnule secondary lobes Cˆ terminal segments), with secondary veins that end just below the secondary lobe apex. The ultimate segments of the Kachchh specimens are nearer in size to the new Hope Bay material, although Gee's C1989) specimens from Hope Bay have smaller secondary lobes. Unfortunately, Bose and Banerji C1984) did not state whether the secondary vein persists to the secondary lobe apex in the Indian material, although they remarked that their material is identical to Harris' C1961) Yorkshire specimens. In view of the poor preservation and small number of specimens, we have followed Halle C1913) and assigned the Hope Bay species to Sphenopteris nordenskjoeldii.

Sphenopteris pecten Halle, emend. nov. Plate 8, ®gure 4 *}1913 Sphenopteris pecten Halle, pl. 4, ®gs 20, 21, 21a. }1989 Sphenopteris pecten Halle; Gee, pl. 4, ®g. 32. Emended diagnosis. Frond segments with winged rachises, secondary pinnae inserted at c. 608 on primary rachis. Pinnules alternate or opposite, arising at 60±908, 3±5 mm apart, length c. ®ve times the width, lobed. Lobes alternate or opposite, falcate, apices acute or obtuse. Pinnule primary vein strong, one secondary vein entering each lobe, persistent almost to the lobe apex.

Holotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20057 CHalle 1913, pl. 4, ®g. 21; Gee 1989, pl. 4, ®g. 32). Designated by Gee C1989).

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Material. Botany Bay: D.8989B.

Description. Sterile primary pinna fragment. Primary pinna rachis up to 2´5 mm wide, secondary pinna rachis up to 1´5 mm wide. Secondary pinna arising at c. 608 from primary pinna rachis. Pinnules either alternate or opposite on secondary pinna rachis, arising at 60±908, 3±4 mm apart. Pinnule length 10±13 mm or more Capices of larger pinnules not preserved). Pinnules lobed; lobes either alternate or opposite, arising at 50±728. Neighbouring lobes connected by lamina, c. 0´1±0´2 mm long. Lobe margins entire, apices acute or subacute. Lobe basiscopic margin expanded, acroscopic margin straight, neither contracted nor expanded. Lobes cuneate, typically falcate; basiscopic margin curving slightly basipetally, acroscopic margin typically straight, occasionally curving slightly acropetally. Lobe length 1´3±1´7 mm, basal width 0´8±1´1 mm, central width 0´6±0´7 mm. Lobe lamina appearing coriaceous, bulging upwards out of matrix. Pinnule primary vein 0´4 mm wide. Secondary veins conspicuous, one entering each lobe, persisting nearly to lobe apex.

Remarks. This species was described by Halle C1913) and Gee C1989) from Hope Bay material. Gee emended Halle's original diagnosis, excluding one of the two pinna fragments ®gured by Halle Cpl. 4, ®g. 20) which she believed to be quite different, its identity remaining `unknown'. The new specimen described here, although poorly preserved, provides new information about the insertion style of the secondary pinnae on the primary pinna rachis. We have therefore further emended the diagnosis of the species to take this into account. These three specimens are all that is known of S. pecten.

Division GYMNOSPERMOPHYTA Order CAYTONIALES Family CAYTONIACEAE Thomas, 1925 Morphogenus SAGENOPTERIS Presl, in Sternberg emend. Rees, 1993b Type. Sagenopteris acuminata Presl, in Sternberg 1838 Cdesignated by Cleal and Rees 2003). This species is a later taxonomic synonym of Sagenopteris nilssoniana CBrongniart) Ward, 1900 Cbasionym Filicites nilssoniana Brongniart, 1825).

Emended diagnosis. See Rees C1993b). Remarks. Leaves and detached lea¯ets of Sagenopteris occur at both Hope Bay and Botany Bay, and at the latter are associated with rare male microsporophylls CCaytonanthus). A similar association has been recorded from nine Northern Hemisphere localities, including the Middle Jurassic ¯ora of Yorkshire CHarris 1964) and has been used as evidence of their close biological af®nity. Taxonomic details of the caytonialean material from Hope Bay and Botany Bay were published by Rees C1993b) and so only an outline is provided here.

Sagenopteris nilssoniana CBrongniart) Ward, 1900 Plate 9, ®gures 1±5 *1825 Filicites nilssoniana Brongniart, p. 218, pl. 12, ®g. 1. §1900 Sagenopteris nilssonia CBrongniart) Ward, p. 352, pl. 56, ®g. 1; pl. 67, ®g. 2.

E X P L A N A T I O N O F P L A T E 8 Fig. 1. Coniopteris sp. A, R.1310.83, Botany Bay; fertile pinna fragment; ´ 2´5. Fig. 2. Coniopteris sp. B, 5622B, Hope Bay; fertile pinna fragment; ´ 2´5. Fig. 3. Sphenopteris nordenskjoeldii Halle, V.63421, Hope Bay; primary pinna fragment showing typical highly dissected pinnules; ´ 2. Fig. 4. Sphenopteris pecten Halle, D8989B, Botany Bay; primary pinna fragment showing secondary pinna attachment and lobed pinnules; ´ 2.

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REES and CLEAL, Coniopteris, Sphenopteris

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}1913 Sagenopteris paucifolia Halle, pl. 1, ®gs 1±5. 1941 Sagenopteris nilssoniana CBrongniart) Ward; Frenguelli, pl. 1, ®gs 1±3; pl. 2, ®gs 1±3; pl. 3, ®gs 1±5. 1941 Sagenopteris sp. Frenguelli, p. 424, pl. 4, ®g. 1. 1956 Sagenopteris nilssoniana CBrongniart) Ward; MeneÂndez, pl. 5; text-®g. 4. 1963 Sagenopteris nilssoniana CBrongniart) Ward; Bonetti, pl. 4, ®gs 1±6. ?1964a Sagenopteris cf. rhoifolia Herbst, ®gs 3, 12. ?1965 Sagenopteris cf. rhoifolia Herbst; Herbst, pl. 2, ®g. 13; pl. 4, ®g. 30. }1989 Sagenopteris paucifolia Halle; Gee, pl. 4, ®g. 33. }1993b Sagenopteris nilssoniana CBrongniart) Ward; Rees, pl. 1, ®gs 1±7; pl. 2, ®gs 1±11; pl. 3, ®gs 1±2. See Harris C1932) and Frenguelli C1941) for other synonyms.

Holotype. Specimen ®gured by Brongniart C1825, pl. 12, ®g. 1). It is in the collections of the Swedish Natural History Museum, Palaeobotanical Section, specimen number SO 87455.

Material. Hope Bay: V.63424, V.63638. Botany Bay: V.63425, V.63639±V.63663, V.63666.

Abridged description Cafter Rees 1993b). Compound palmate leaf; petiole typically bearing four lea¯ets Coccasionally three) at its apex. Lowermost pair of lea¯ets often more ovate than uppermost pair. Leaves usually represented by detached, lanceolate or ovate, lea¯ets. Lea¯et apices typically acute, occasionally obtuse. Lea¯ets 6±87 mm or more long, commonly c. 25±65 mm, maximum width 3±31 mm, commonly c. 10±20 mm. Lea¯et margins typically entire or slightly undulating. Occasionally, otherwise entire lea¯ets are variably lobed. Lea¯et midrib distinct, slightly curving or sinuous, persisting to 35±90 per cent of lea¯et length. Midrib maximum width 0´3±1´9 mm. Lateral veins arising from midrib at 3±208, curving basipetally to reach margins at 30±658 Cmeasured in middle portion of lea¯et). Veins fork and anastomose irregularly at varying distance from midrib, forming elongate meshes; veins ending freely at lea¯et margins. Vein mesh width 0´2±0´7 mm. Vein density Cin middle portion of lea¯et) 14±35 per cm, typically 20±30 per cm. Vein density near midrib Cmeasured perpendicular to veins, in middle portion of lea¯et) 12±35 per cm, typically 20±30 per cm.

Remarks. Most specimens studied from Hope Bay and Botany Bay have entire or slightly undulating margins, although some are lobed. Typically, only single lea¯ets are seen, although small complete leaves bearing four Csometimes three) lea¯ets are occasionally preserved. The presence of complete leaves, the asymmetry of the lea¯ets, and the venation pattern place these specimens ®rmly within Sagenopteris. If only entire-margined and heavily-lobed lea¯ets had been collected, there would be a case for separating them as two distinct species. However, the extreme-lobed lea¯et Cwith six lobes on each margin) can be linked to those with entire margins through a series of intermediates. The smaller entire-margined lea¯ets are also linked to the larger ones through a series of intermediates. Signi®cantly, entire-margined lea¯ets are identical in venation pattern and density to those of similar size that have lobed margins. Additionally, all of the Sagenopteris specimens from Botany Bay were found in a 1-m-thick band in the sampled section, and included the complete range of lea¯et-form. Although Halle C1913, p. 9) noted that some of his Hope Bay Sagenopteris specimens resemble S. nilssoniana, he assigned them to S. paucifolia, stating that `since S. paucifolia is represented by some typical specimens whereas S. nilssoniana is not, it seems better to refer these questionable specimens [resembling S. nilssoniana] also to the former species [S. paucifolia]' Csee also Gee 1989). However, Rees

E X P L A N A T I O N O F P L A T E 9 Figs 1±5. Sagenopteris nilssoniana CBrongniart) Ward. 1, V.63657; leaf with four morphologically-similar lea¯ets. 2, V.63640; large lea¯et, showing anastomosing venation. 3, V.63648; leaf comprising four lea¯ets, the lowermost pair being shorter and more ovate than the uppermost pair. 4, V.63642; lea¯et with variably lobed margins. 5, V.63646; leaf comprising three deeply-lobed lea¯ets. All ´ 2. Fig. 6. Caytonanthus sp., V.63664; main axis with short and long lateral branches bearing synangia; ´ 3. All specimens from Botany Bay.

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REES and CLEAL, Caytonanthus, Sagenopteris

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:05 ALDEN 36 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 C1993b) has shown that the linear-lanceolate lea¯ets believed to be typical by Halle are actually rather rare here, and are better assigned to S. nilssoniana. Indistinguishable are Early Jurassic specimens from Piedra Pintada, Argentina, assigned to S. nilssoniana by Frenguelli C1941). Lea¯et margins in the Argentine specimens are either slightly or markedly undulating, and one specimen has entire margins except for a wide single lobe with a rounded apex CFrenguelli 1941, p. 415). From the same locality, Frenguelli described and illustrated another lea¯et as Sagenopteris sp. This is almost identical to some of the lobed specimens described by Rees C1993b) and can also be assigned to S. nilssoniana, a possibility at which Frenguelli C1941, p. 425) himself hinted. The only similar species with lobed lea¯et margins is Sagenopteris mclearni Berry from the Cretaceous of North America Cas discussed by Frenguelli 1941) but its margins are deeply and regularly lobed, appearing pinnati®d. The morphology and cuticle of Sagenopteris undulata Halle, 1910 from the Rhaeto- Liassic of Sweden Csee also Lundblad 1950) is very similar to S. nilssoniana and may be a later synonym CHarris 1964).

Morphogenus CAYTONANTHUS Harris emend. Harris, 1964 Type. Caytonanthus arberi CThomas) Harris, as designated by Harris C1964).

Caytonanthus sp. Plate 9, ®gure 6 }1993b Caytonanthus sp.; Rees, pl. 3, ®gs 3±6.

Material. Botany Bay: V.63664, V.63665.

Description Cfrom Rees 1993b). Microsporophyll with main rachis bearing short and long lateral branches that are simple or divided into branchlets. Each ultimate branchlet bears one synangium at its apex. Synangia narrowly ovate, up to 3´5 mm long by 1´5 mm wide in their central regions. Dehiscence line of pollen sacs visible along longitudinal axis of synangium, not reaching to synangium base or apex. Surfaces showing elongated cells running parallel to longitudinal axes of synangia.

Remarks. Harris C1937) erected Caytonanthus for the microsporophyll believed to form part of `the Caytonia plant', along with the leaf CSagenopteris), and the megasporophyll CCaytonia). Although details of the pollen sacs and pollen are not preserved in the best Botany Bay specimen CV.63664), it agrees in its synangial attachment and morphology Cincluding the dehiscence line and elongate cell walls) with the emended generic diagnosis given by Harris C1964). The specimen came from the same 1-m thick band at Botany Bay that yielded the Sagenopteris leaves. This is the ®rst record of a caytonialean reproductive organ from Gondwana Ccf. Anderson and Anderson 1985).

Class CYCADOPSIDA Order CYCADALES Family unknown Morphogenus CTENIS Lindley and Hutton emend. Harris, 1964

Type. Ctenis sulcicaulis Phillips, 1829, as designated by Harris C1964).

Ctenis sp. cf. exilis Harris, 1964 Plate 10, ®gures 3±5 Material. Botany Bay: V.63766 to V.63768.

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Description. Leaf once-pinnate, bearing pinnae with lobed Cserrate/toothed) margins. Leaf rachis 1±2 mm wide. Pinnae opposite on rachis, arising at c. 908, up to 54´5 mm long Capices not preserved) and 14±16 mm wide at their base. Pinna width Cmeasured in central region) c. 15 mm. Pinna margins subparallel, irregularly lobed. Lobes dividing into smaller segments in basal region of pinna, undivided in apical region. Lobe apices acute, directed towards pinna apex, occasionally appearing obtuse where covered by rock matrix. Apices rimmed by a narrow vein, continuous around the lobe margins. Lobes 1´5±14´5 mm long, 0´5±3´0 mm wide. Pinna venation coarse; several veins of equal strength arising near-parallel from pinna base, subsequently dichotomising and anastomosing at irregular intervals. Pinna central veins remaining subparallel from base to apical region, lateral veins diverging from base at c. 15±258 into pinna lobes. Veins subparallel in large lobes then subsequently diverging, with one vein entering each smaller segment and persisting to its apex. Vein density ranging from 6 per cm Cnear pinna base) to 12 per cm Cin apical region), typically 9±11 per cm.

Remarks. This species is represented at Hope Bay and Botany Bay by rare foliage fragments in which the pinnae have irregularly lobed margins, and veins which typically and frequently anastomose. The specimens can be assigned to the cycad genus Ctenis based on their macroscopic features, especially the anastomosing venation. Those cycadophyte genera with otherwise similar pinnae, such as the cycad Pseudoctenis and the bennettite Pterophyllum, rarely if ever show anastomosing veins CHarris 1964, 1969). The Antarctic specimens are also interpreted as probably from a cycad in view of the similarity to Ctenis exilis leaves from the Yorkshire Jurassic, which are regarded as a cycad based on cuticular evidence CHarris 1964). The combination of pinnate leaves with lobed pinna margins and forking or anastomosing veins is rare in Mesozoic ¯oras, and C. exilis is the only well-documented species to show these features together. The pinnae of the Yorkshire specimens are generally smaller Cless than 7 mm wide), but size difference alone does not justify a species separation. Ctenis exilis proper has not been described previously from a Gondwanan ¯ora. Ctenis harrissii Vakhrameev and C. stanovensis Vakhrameev, both from the Lower Cretaceous of Russia, also have lobed pinna margins but are not well documented species Csee Kimura and Sekido 1971 for a review in English). Chilinia ctenioides Li Xingxue and Ye Meina, 1980 from the Lower Cretaceous of Jilin, nort-east China, is indistinguishable from Ctenis exilis except that it also has larger pinnae, which is insuf®cient for assigning them to a separate species or even genus. Li and Ye C1980) generically separated the Jilin specimens Cas well probably as Ctenis exilis) from Ctenis largely because of their toothed pinnae. However, Recent cycad genera Ce.g. Encephalartos) include species with both entire and toothed pinnae CHarris 1964; Giddy 1974) and the generic distinction on this character alone seems unjusti®ed. Other cycadophyte leaves with lobed margins have been described as Neozamites Vakhrameev and Encephalartites Vakhrameev CKimura and Sekido 1971), but the venation is simple or forked Cnever anastomosing).

Morphogenus PSEUDOCTENIS Seward, 1911 Type. Pseudoctenis eathiensis CRichards) Seward, 1911.

Remarks. Without cuticles, it can be dif®cult to distinguish morphologically between fronds of the cycad Pseudoctenis Seward and the bennettite Pterophyllum Brongniart. Halle C1913) assigned this Antarctic material to a new species, which he included in Pseudoctenis. In the absence of any evidence one way or the other, we have essentially followed Halle's taxonomic treatment. However, as we cannot be certain that the species is a true cycad, we have placed a `?' after the generic name.

Pseudoctenis? ensiformis Halle, 1913 Plate 11, ®gures 1±4; Text-®gure 4 *1913 Pseudoctenis ensiformis Halle, pl. 6, ®g. 8. }1913 Pseudoctenis cfr. Medlicottiana COldham and Morris) Halle C?non Oldham and Morris), pl. 6, ®gs 9±10.

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?1981 Pterophyllum footeanum Feistmantel; Bose and Banerji 4?non Feistmantel), text-®g. 14B. ?1981 Pterophyllum morrisianum Oldham in Oldham and Morris; Bose and Banerji 4?non Oldham), text- ®g. 21A±B. ?1982 Pseudoctenis grossa Holmes, ®g. 11A±B. T}1989 Pseudoctenis ensiformis Halle; Gee, pl. 5, ®g. 48.

Holotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 2000124.

Material. Botany Bay: D.8864A, D.8951.13B, D.8954.3B, D.8956.17B, D.8956.32A, D.8956.71, D.8956.75A, D.8958.5A, D.8962.8B, D.8987B, D.9002.2A, D.9002.3A, D.9002.8A, D.9002.10A, D.9024B, D.9025A.

Description. Leaf once pinnate, pinnae arising laterally or slightly above midline of rachis. Rachis up to 8 mm wide, typically 2±5 mm. Pinnae alternate to opposite, arising at 25±908, typically 55±858, separate or connected by basal lamina. Pinnae 1´0±9´5 mm apart on leaf rachis. Pinna margins entire, near-parallel beyond basal expansion, then converging towards apex. Pinna bases typically expanded basiscopically and acroscopically. Occasionally, bases appear constricted basiscopically and acroscopically, or expanded basiscopically and contracted acroscopically. Pinna apices acute 4only visible in smaller pinnae). Pinnae up to 88 mm long, 3±34 mm 4typically 4±15 mm) wide at their bases. Pinna width 4measured where central and lateral veins become parallel) 1´5±22´0 mm 4typically 3±10 mm). Ratio of pinna length to width 4measured where veins become parallel) in small, complete, pinnae 9±12. Pinna venation coarse, several veins of equal strength arising from pinna base. Basiscopic veins curving parallel to basiscopic margin, acroscopic veins parallel to acroscopic margin. Central veins straight, parallel or subparallel. Basiscopic and acroscopic veins becoming parallel or subparallel to central veins c. 10 mm from pinna base in larger pinnae, and 1±5 mm from base in smaller pinnae. Veins typically simple, occasionally bifurcating at varying distance from pinna base; rarely, anastomosing. Vein density 4measured where central and lateral veins become parallel) 6±35 per cm 4typically 10±25 per cm); number of veins per pinna 4±13 4typically 6±11).

Remarks. Gee 41989) transferred to P. ensiformis the Hope Bay specimens identi®ed by Halle 41913) as Pseudoctenis cf. medlicottiana. This is supported by the new material, which includes a transitional range between the characters used by Halle to separate the species: the pinnae have bases that are either constricted or expanded 4Text-®g. 4), and the veins range from coarse to ®ne. According to Gee 41989) the Hope Bay specimens are similar in the general aspect of the pinnae and venation to the specimens described as Pterophyllum medlicottianum from the Rajmahal Hills and Satpura Basin of India 4Bose and Banerji 1981). Gee distinguished the Hope Bay specimens, because she claimed their lateral veins commonly fork, those of P. medlicottianum remaining simple. However, the new fossils from Hope Bay and Botany Bay show mainly simple veins, forking lateral veins being far less frequent than suggested by Gee 41989). Furthermore, the Indian specimens are associated with other fronds 4Pterophyllum footeanum and P. morrisianum), which show occasional vein bifurcations but which are otherwise identical to P. medlicottianum. The Indian material clearly needs further investigation, but it seems clear that the degree of vein bifurcation appears not to be a reliable taxonomic character. Until such work is done, it will be best if the Hope Bay and Botany Bay material is kept taxonomically separate and assigned to Pseudoctenis? ensiformis, but there must be a strong possibility that this species will eventually prove synonymous with P. medlicottianum, P. footeanum and P. morrisianum. Because of the wide range of morphological characters, it is arguable that several species of Pseudoctenis 4and/or Pterophyllum) are present in the Hope Bay and Botany Bay ¯oras. However, the

E X P L A N A T I O N O F P L A T E 10 Figs 1±2. Dicroidium feistmantelii 4Johnston) Gothan. 1, V.63763; frond segment showing variation in pinna attachment and pinnule morphology; ´ 1´5. 2, V.63764; pinna segment showing pinnule venation; ´ 3. Figs 3±5. Ctenis sp. cf. exilis Harris. 3±4, V.63766; 3, pinna segment showing lobed margins; ´ 1´75; 4, V.63766; detail showing anastomosing venation; ´ 2. 5, V.63768; leaf fragment showing attachment of pinnae to the leaf rachis; ´ 1. All specimens from Botany Bay.

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REES and CLEAL, Ctenis, Dicroidium

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TABLE 1. Pinna characteristics in Zamites, Otozamites and Ptilophyllum Cmodi®ed from Person and Delevoryas 1982 and Gee 1989).

Zamites Otozamites Ptilophyllum

Acroscopic basal margin Typically contracted Contracted Contracted Basiscopic basal margin Typically contracted Contracted Decurrent Curvature of acroscopic veins Basipetal Acropetal Basipetal Curvature of basiscopic veins Acropetal Acropetal Basipetal Symmetry of pinna base Typically symmetrical Asymmetrical Asymmetrical Presence of auricle Typically absent On acroscopic margin Typically absent

occurrence of specimens with intermediate characters provides evidence for combining the extreme forms within the same species; a near-continuous range of pinna widths and vein concentrations is seen.

Class GNETOPSIDA Order BENNETTITALES Family unknown Remarks. In the absence of cuticles, the following three species can only tentatively be regarded as bennettite foliage. They have been included here largely for pragmatic reasons: the historical precedence of the views of Halle C1913) and Gee C1989), and the absence of any suitable form-genus for such cycadophyte foliage where cuticles are lacking Cin contrast to the situation with Taeniopteris, see below). Neither of these reasons is particularly persuasive. However, the only alternative actions would be to propose new form-genera for such foliage lacking cuticles, which at this stage we are reluctant to do, or to transfer the species to cycad genera, for which there is as little justi®cation as there is for retaining them Ctentatively) as bennettites. Our chosen route at least has the merit of minimising nomenclatural disruption. Without cuticles, the distinction of Zamites, Otozamites and Ptilophyllum can be dif®cult. The problems are particularly acute when the pinna base is weakly developed or partially covered by rock matrix CHalle 1913; Harris 1969). However, Person and Delevoryas C1982) have proposed that a combination of the venation and basal shape of the pinnae can be used to separate Zamites, Otozamites and Ptilophyllum Csee Table 1). Halle C1913) described four species of Zamites, six of Otozamites and one of Ptilophyllum from Hope Bay. Gee C1989) revised these using the Person and Delevoryas C1982) scheme and recognised four species of Zamites and two of Otozamites. We recognise here just one species of Zamites and two of Otozamites following the discovery of specimens at Hope Bay and Botany Bay that are intermediate between at least some of Halle's and Gee's species. The following is a key for distinguishing these species.

1. Pinna bases symmetrical. Basal acroscopic veins curving basipetally, basiscopic veins curving acropetally. Ratio of pinna length to basal width typically between 5 and 10. From 6 to 10 veins per pinna, 4 to 7 veins per mm ...... Zamites? antarcticus Pinna bases typically asymmetrical; acroscopic margin expanded, forming a basal auricle, basiscopic margin typically straight. Basal acroscopic veins curving acropetally, basiscopic veins typically curving acro- petally ...... 2 COtozamites? spp.)

E X P L A N A T I O N O F P L A T E 11 Figs 1±4. Pseudoctenis? ensiformis Halle. 1, D.8864A; leaf fragment showing typical pinnae with decurrent basiscopic margins and distorted pinnae with apparently constricted bases; ´ 1. 2, D.8951.13B; leaf fragment; ´ 1. 3, D.9002.3A; broad pinnae showing basal decurrency and venation; ´ 1´5. 4, D.9024B; apical region of leaf fragment bearing narrow pinnae; ´ 1´5. All specimens from Botany Bay.

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REES and CLEAL, Pseudoctenis?

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2. Pinna bases typically asymmetrical; acroscopic margin expanded only slightly, forming a weak auricle Cregardless of pinna position on leaf), bases occasionally symmetrical, expanded slightly both acro- and basiscopically. Pinna acroscopic and basiscopic marginal veins diverging from base at shallow angles Ci.e. acroscopic veins curving only slightly acropetally). Ratio of pinna length to basal width typically 4±8 ...... Otozamites? latior Pinna bases asymmetrical; acroscopic margin expanded, forming a pronounced auricle in pinnae from central region of leaf Cauricle often less marked in pinnae from basal and apical regions of leaf). Pinna acroscopic veins diverging from base at wider angles than basiscopic veins Ci.e. acroscopic veins typically curving strongly acropetally). Ratio of pinna length to basal width typically 2±4 ...... Otozamites? linearis

Morphogenus ZAMITES Brongniart emend. Harris, 1969

Type. Zamites gigas CLindley and Hutton) Morris emend. Harris, 1969.

Zamites? antarcticus Halle, 1913 Plate 12, ®gures 1±4 *}1913 Zamites antarcticus Halle, pl. 7, ®gs 19±20, 23±24, 28, 28a; text-®g. 13a±d. }1913 Zamites Anderssonii Halle, pl. 7, ®gs 13, 22; text-®g. 12b±c. }1913 Zamites pachyphyllus Halle, pl. 7, ®gs 14±16; pl. 8, ®g. 1a; text-®g. 14. p}1913 Otozamites Hislopi Feistmantel; Halle, pl. 7, ®g. 21. }1913 Ptilophyllum CWilliamsonia?) pectinoides CPhillips) Morris; Halle, pl. 7, ®gs 25±27. p}1972 Ptilophyllum antarcticum CHalle) Archangelsky and Baldoni Cun®gured Hope Bay material only). }1989 Zamites anderssonii Halle; Gee, pl. 6, ®g. 55. }1989 Zamites antarcticus Halle; Gee, pl. 7, ®gs 56±57. }1989 Zamites pachyphyllus Halle; Gee, pl. 7, ®gs 58±59.

Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20117 CHalle 1913, text- ®g. 13c±d). Designated by Gee C1989).

Material. Hope Bay: 5953, V.63427, D.5.1. Botany Bay: D.8937.1A, D.8937.2B, D.8937.4A, D.8937.6B, D.8937.9B, D.8937.11A, D.8937.12A, D.8937.12B, D.8937.14B, D.8957.5B.

Description. Leaf once pinnate, pinnae arising on upper surface of rachis, at median line. Pinnae arising at 55±908, typically 60±758. Pinnae typically alternate, occasionally opposite or subopposite. Neighbouring pinnae overlapping slightly or up to c. 1 mm apart. Pinna shape variable; margins parallel or subparallel for 50±80 per cent of pinna length before converging to apex, or else converging gradually from base to apex. A thin rim is visible rarely along margins. Pinnae 9´5±15´5 mm long Ctypically 12±14 mm), basal width 1´0±2´5 mm, central width 1±2 mm. Ratio of pinna length to basal width 4´6±12´9, typically 5±10. Ratio of pinna length to central width 4´8±14´2, typically 7±10. Pinna apices acute to obtuse. Pinna bases symmetrical; either equally expanded, straight, or equally contracted, not decurrent on leaf rachis. Acroscopic veins curving basipetally at the pinna base, basiscopic veins curving acropetally, central veins straight. Central veins persisting to pinna apex, near-parallel. Lateral veins diverging at narrow angles from pinna base, reaching margins at least 35 per cent of distance from pinna base to apex. Veins bifurcating occasionally, at varying distance from pinna base. Vein density Cmeasured in central region of pinna) 4±7 per mm C6±10 veins per pinna).

Remarks. Three species recognised from Hope Bay by Halle C1913) and Gee C1989) are combined here within Zamites? antarcticus. Of those three species, Gee C1989) indicated that Z. antarcticus was the most abundant at Hope Bay, with Z. anderssonii being represented by only two specimens and Z. pachyphyllus

TEXT-FIG. 4. Pseudoctenis? ensiformis Halle, Botany Bay; details of pinna insertion and venation pattern. A, 8956.71B; B, D.8962.8B; C, E, D.8864.A; D, D.8956.71A; F, D.8958.5A; G, D.9025A; H, D.9002.8A. Upper scale bar corresponds to A±F, lower scale bar to G±H.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:06 ALDEN 44 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 by seven. Gee suggested that Z. anderssonii might be merely a variant of Z. antarcticus, being only distinguished by a slight difference in venation density C3±4 per mm and 5±6 per pinna in the former, 4±5 per mm and c. 9 per pinna in the latter). The new material described here shows a continuous range of variation in nervation density of 4±7 per mm and 6±10 per pinna, con®rming that these morphotypes indeed merely represent variation within a single species. Gee C1989) described Z. pachyphyllus as having the same pinna shape and venation density as Z. antarcticus. The former was distinguished mainly on the presence of thin wings of lamina rimming each of the pinnae, and the attachment of the pinnae to the marginal third of both edges of the rachis. However, the presence of marginal wings of lamina is almost certainly a compression feature induced during fossilisation, and can also be seen in Otozamites latior and O. linearis Csee Pl. 13, ®gs 3, 5; Pl. 14, ®g. 4). Gee's evidence as to pinna attachment is also unconvincing, as in most of her specimens the pinna bases are absent Ce.g. Gee 1989, pl. 7, ®g. 59). In one of her few examples that shows the pinnae attached to the rachis CGee 1989, pl. 7, ®g. 58, left side) they are clearly attached to the upper side of the rachis. Furthermore, one of her illustrated specimens shows, towards the leaf apex, pinna bases that are almost in contact with those on the other side of the rachis, covering it almost to its median line. Taking all these factors together, there seems little justi®cation for not including Z. pachyphyllus within Zamites? antarcticus. Archangelsky and Baldoni C1972) described a species of Ptilophyllum from the Lower Cretaceous Baquero Formation, Santa Cruz, Argentina. They believed their specimens, yielding cuticles, to be closely similar macroscopically to the Z. antarcticus impressions from Hope Bay, and assigned both these and the Argentine material to the new combination Ptilophyllum antarcticum. Gee C1989), recognising that the pinna bases of the Hope Bay specimens were fully compatible with that of Zamites as de®ned by Harris C1969) and Person and Delevoryas C1982), retained Halle's C1913) original designation as Z. antarcticus. She also included the Argentine cuticle-bearing specimens in Z. antarcticus, remarking that `this species, described with the details of the cuticle by Archangelsky and Baldoni C1972), thus pertains to the genus Zamites' CGee 1989, p. 191). However, the Argentine specimens have asymmetrical pinna bases in which the basiscopic basal margins of the pinnae are decurrent on the rachis, in addition to having parallel veins where both the acroscopic and basiscopic veins curve basipetally CArchangelsky and Baldoni 1972; Baldoni 1979; Baldoni and Taylor 1983) and had thus been correctly placed in Ptilophyllum as de®ned by Harris C1969) and Person and Delevoryas C1982). The Argentine material cannot, therefore, be regarded as conspeci®c with Z. antarcticus and should probably be assigned to a new species. This species represents a good example of the problem of separating Zamites from Ptilophyllum. Their distinction is probably arti®cial anyway and it is likely that they belonged to a `natural' genus with Williamsonia and Weltrichia fructi®cations. However, the preservation of our material is insuf®cient basis for a proper revision of this problem and we have therefore followed the traditional taxonomic approach.

Morphogenus OTOZAMITES Braun, 1843 Type. Otozamites obtusus CLindley and Hutton) Brongniart, 1849.

Otozamites? latior Saporta, 1875 Plate 13, ®gures 1±5 *1875 Otozamites latior Saporta, p. 130, pl. 97, ®g. 1; pl. 98, ®gs 1±3. 1877 Otozamites Hislopi Oldham ex Feistmantel, p. 92, pl. 6, ®gs 3±4; pl. 11, ®g. 1.

E X P L A N A T I O N O F P L A T E 12 Figs 1±4. Zamites? antarcticus Halle. 1, 3, Hope Bay; symmetrical pinna bases; 1, 5953; 3, V.63427. 2, 4, Botany Bay; 2, D.8937.14B; pinna venation with acroscopic veins curving basipetally and basiscopic veins curving acropetally; 4, D.8937.12A; symmetrical pinna bases and characteristic venation. All ´ 2.

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}1913 Zamites pusillus Halle, pl. 7, ®g. 12; text ®g. 12a. }1913 Otozamites latior Saporta; Halle, pl. 7, ®g. 6. p}1913 Otozamites Hislopi Feistmantel; Halle, pl. 7, ®gs 5, 7. }1989 Otozamites rowleyi Gee, pl. 6, ®gs 53±54. }1989 Zamites pusillus Halle; Gee, p. 193, pl. 7, ®g. 60.

Types. The present location of the Saporta collection is unknown and the syntypes are presumed lost. A neotype must therefore be designated. However, the Antarctic material is not suitable due to its preservation, and so we make no proposals here.

Material. Hope Bay: D.6.6 Cpart and counterpart), D.32.15, D.32.23, 8059, 8092. Botany Bay: D.8937.13, D.8957.1A, D.8957.4B.

Description. Leaf once pinnate, pinnae attached to upper surface of rachis, at median line. Pinnae arise at 40±908, typically 50±708. Pinnae typically alternate, occasionally subopposite. Pinna shape variable; margins parallel or subparallel Cbeyond basal acroscopic expansion) for 50±80 per cent of pinna length, before converging to apex, or else margins converge gradually from base to apex. Thin rim Cc. 0´1±0´2 mm wide) rarely visible along margins. Except at leaf base and apex, pinnae 6´5±23 mm long Ctypically 8±14 mm), 1´5±4 mm wide at base, 1±3 mm wide at middle. Ratio of pinna length to basal width 2´2±10, typically 4±8. Ratio of pinna length to central width 2´5±15, typically 7±11. Pinna apices acute to obtuse. Pinna bases typically slightly asymmetrical; acroscopic margin expanded, forming a weak auricle, basiscopic margin straight Cboth margins slightly contracted or straight below level of acroscopic expansion). Pinna bases occasionally symmetrical, expanded slightly both acroscopically and basiscopically. Acroscopic veins curve slightly acropetally at the pinna base, basiscopic veins also typically curve slightly acropetally, occasionally either straight or else curve slightly basipetally. Central veins parallel or subparallel, persisting to pinna apex; lateral veins diverge at narrow angles from pinna base. Veins bifurcate occasionally, at varying distance from pinna base. Vein density Cmeasured in central region of pinna) 3±7 per mm C5±10 veins per pinna).

Remarks. Some of the specimens included here are similar to Zamites, having symmetrical pinna bases that are expanded slightly both acro- and basiscopically. However, the acroscopic veins always curve acropetally, a characteristic feature of Otozamites. In our view, venation is normally a more reliable taxonomic character than the shape of the pinna base, which can be vulnerable to distortion during leaf transportation and burial. We have therefore retained this species in Otozamites. Halle C1913) assigned a single leaf to a new species, Zamites pusillus. Gee C1989, p. 19.3) redescribed the specimen, noting that its pinna bases are `more or less symmetrical', although it is `somewhat unusual in having acroscopic veins which curve acropetally'. Gee described its vein density as 4±5 per mm, about 8±9 per pinna, which is fully within the range of variation of O. latior as described here. There seems little reason, therefore, for separating Halle's specimen from O. latior. Gee C1989) erected a new species, Otozamites rowleyi, for specimens from Hope Bay which Halle C1913) had previously assigned to O. latior and O. hislopii Cin part). However, Gee C1989, p. 190) also stated that `the fragmentary leaf described by Halle as Otozamites latior resembles the other, more complete leaves of O. rowleyi. . . .they are considered to be members of the same species'. Otozamites latior was erected by Saporta C1875), and it is to this species that we reassign the specimens from Hope Bay which Gee C1989) described as O. rowleyi. Since O. latior has nomenclatural priority over both O. hislopii and O. rowleyi, the original Hope Bay material, as well as that described here, should be assigned to this species.

E X P L A N A T I O N O F P L A T E 13 Figs 1±5. Otozamites? latior Saporta. 1, 4, D.6.6; 1, leaf fragment showing basal and more distal pinna forms; ´ 1; 4, close-up of venation with basiscopic and acroscopic veins curving slightly acropetally; ´ 3. 2, 8092; complete leaf showing variation in pinna morphology; ´ 1. 3, 5, 8059; 3, leaf fragment showing venation Cwith basiscopic and acroscopic veins curving slightly acropetally) and marginal rims on pinnae; ´ 2; 5, close-up of marginal rims; ´ 3. All specimens from Hope Bay.

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REES and CLEAL, Otozamites? Otozamites? linearis Halle, 1913 Plate 14, ®gures 1±5 *}1913 Otozamites linearis Halle, pl. 7, ®gs 1±4, 8, 9, 9a, 11; text-®g. 15. }1913 Otozamites spp. Halle, pl. 7, ®gs 10, 18. ?1976 Otozamites imbricatus; Maheshwari and Singh, pl. 2, ®gs 10±11; text-®g. 2. T} 1989 Otozamites linearis Halle; Gee, pl. 6, ®gs 50±52. Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20102 CHalle 1913, text- ®g. 15; Gee 1989, pl. 6, ®g. 51).

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Material. Hope Bay: D.11.2, D.39.20, 5976, 8053, V.63428. Botany Bay: D.8926A, D.8944.8A, D.8944.11A, D.8944.17A, D.8977.1/bB, D.8977.4A, D.8977.4B, D.8979.4A, D.8979.5B.

Description. Leaf once-pinnate; pinnae attached to upper surface of rachis, at median line, typically touching or overlapping slightly at their bases. Pinnae arise at 40±908, typically 60±808. Pinnae typically alternate, occasionally subopposite. Pinna margins parallel or subparallel Cbeyond acroscopic expansion) to 70±80 per cent of distance from base to apex, then converging to apex. Thin rim Cc. 0´1±0´2 mm wide) rarely visible along margins. Pinnae 5´5±24 mm long Ctypically 6±10 mm), 2±5 mm wide at base, 1´5±3´5 mm in middle. Ratio of pinna length to basal width 1´8±7, typically 2±4. Ratio of pinna length to central width 2±10, typically 2±5. Pinna apices subacute to obtuse. Pinna bases asymmetrical; acroscopic margin expanded, forming a pronounced auricle Cvisible in pinnae from central region of leaf, auricle often less marked in pinnae from basal and apical regions), basiscopic margin typically straight or slightly contracted Crarely, slightly expanded). Pinna bases often constricted slightly, below level of acroscopic expansion. Acroscopic veins typically strongly curved acropetally at the pinna base, basiscopic veins typically curved slightly acropetally, occasionally remaining straight. Central veins near-parallel, persisting to pinna apex, acroscopic veins diverging from base at wider angles than basiscopic veins. Veins bifurcate occasionally, at varying distance from pinna base. Vein density Cmeasured in central region of pinna) 4±9 per mm C8±17 veins per pinna).

Remarks. We include in this species leaves bearing elongate pinnae with pronounced acroscopic auricles, and leaves bearing shorter, more oblong pinnae with weakly developed acroscopic auricles. Gee C1989) described intermediate specimens linking these two morphotypes, and in the new material described here there are examples of both types of pinnae occurring in the same leaf Ce.g. Pl. 14, ®gs 2±3).

CYCADOPHYTE FOLIAGE incertae sedis Morphogenus TAENIOPTERIS Brongniart, 1831

Type. Taeniopteris vittata Brongniart, 1831.

Remarks. The typi®cation and circumscription of this form-genus was discussed by Cleal and Rees C2003), who interpreted it as a morphogenus of entire cycadophyte leaves, which cannot be assigned to Nilssonia, Nilssoniopteris or Nipaniophyllum because of the absence of cuticular evidence.

Taeniopteris taeniopteroides CHalle) comb. nov.

Plate 15, ®gures 1±4; Text-®gure 5A±D *1913 Nilssonia taeniopteroides Halle, pl. 5; pl. 6, ®gs 1±7; text-®g. 11a±c. ?1944 Nilssonia cf. taeniopteroides Halle; Frenguelli, pl. 4, ®gs 1±2. ?1976 Taeniopteris densinervis Feistmantel; Maheshwari and Singh C?non Feistmantel), pl. 1, ®g. 5; text-®g. 4. ?1977 Sueria rectinervis Baldoni, pl. 1, ®g. 1. ?1981 Taeniopteris kutchensis Bose and Banerji, pl. 1, ®gs 7±9; pl. 5, ®g. 26; text-®gs 2A±D, 9A. ?1981 cfA Taeniopteris daintreei McCoy; Jefferson, pl. 4.10, ®gs 1±3; pl. 4.11, ®gs 1±4. ?1982 Taeniopteris sp. Holmes, ®g. 11C. ?1982 Taeniopteris oaxacensis Person and Delevoryas, pl. 8, ®g. 45. ?1984 Taeniopteris kutchensis Bose and Banerji; Bose and Banerji, text ®gs 58A±D, 59D.

E X P L A N A T I O N O F P L A T E 14 Figs 1±5. Otozamites? linearis Halle. 1, 5, 8053; 1, leaf fragment; ´ 1´5; 5, close-up showing pronounced acroscopic auricles and acroscopic curvature of the basiscopic Cweakly curving) and acroscopic Cstrongly curving) veins; ´ 3. 2, D.11.2; leaf fragment showing shorter basal and longer distal pinnae; ´ 1´5. 3, V.63428; leaf fragment showing variation in pinna morphology; ´ 2´5. 4, D.39.20; leaf fragment comprising pinnae with pronounced acroscopic auricles and thin marginal rims; ´ 2. All specimens from Hope Bay.

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?1988 Taeniopteris lata; Sengupta, pl. 8, ®g. 21. }1989 Nilssonia taeniopteroides Halle; Gee, pl. 6, ®g. 49.

Lectotype. Swedish Natural History Museum, palaeobotanical Section, specimen number 20100 CHalle 1913, text-®g. 11b; pl. 5). Designated by Gee C1989).

Material. Hope Bay: D.34.8, D.34.9, D.39.21, 8056, 8093 [MF1ACa±e), MF4A, MF6ACa±d), housed in the Department of Geology, Universidade Federal do Rio de Janeiro]. Botany Bay: D.8977.9A, D.8982.2B.

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Description. Leaf long and narrow, simple, petiolate. Margins entire, diverging from leaf base, near-parallel in central regionofleaf, then converginggradually toleafapex.Leaf apexobtuse.Leaf base asymmetrical onpetiole; anglebetween margins and rachis 30±408 and 10±208 respectively. Only two complete leaves preserved, 48 mm and 120 mm long, with maximum widths of 9´5 mm and 20 mm respectively; ratio of leaf length to maximum width 5±6. Leaf fragments 17±100 mm wide, typically 25±45 mm Cestimated length of widest leaf c. 500±600 mm), leaf rachises 0´1±7 mm wide. Lamina appears to arise either laterally or from the upper surface of rachis, depending upon level of fracture plane through leaf. Ratio of leaf width to rachis width 6±35 Ctypically 10±20), re¯ecting varying exposure of rachis. Lateral veins typically simple, occasionally forking Crarely, anastomosing), parallel, persisting to margins CText-®g. 5A±D). Veins forking at varying distance from rachis to margins, but most veins forking near rachis. Veins arising from rachis Cin middle portion of leaf) at 60±908, typically 70±858. Angle decreasing towards leaf margins; from 50±808, typically 55±708, at two-thirds the distance from rachis to margins. Veins arising from rachis at narrower angles in basal and apical portions of leaf. Vein density near rachis 13±32 per cm, typically 15±20 per cm. Vein density near margins 16±42 per cm, typically 16±25 per cm.

Remarks. Gee C1989) continued Halle's C1913) assignment of this species to Nilssonia, and thereby the cycad order Nilssoniales, because of the adaxial attachment of the lamina and the simple venation. As pointed out by Harris C1969), however, the bennettitalean frond Nilssoniopteris can also have simple veins. The assignment of this species to one or other of these genera must, therefore, be based on the position of insertion of the pinnae on the rachis. In impression material such as that from Hope Bay and Botany Bay, this can be very dif®cult to ascertain and the apparent insertion can depend on where through the leaf the fracture-plane has passed. Consequently, we feel it safer to assign Halle's species to Taeniopteris, which makes no assumption as to this feature. Specimens of T. taeniopteroides from both Hope Bay and Botany Bay show considerable variation in leaf width, ranging from 9´5 to 100 mm. Halle C1913) and Gee C1989) both commented on this variation, although neither had quite such large specimens as found in the present study. The larger specimens are of the type assigned to the separate genus Macrotaeniopteris by Schimper C1869). As pointed out by Person and Delevoryas C1982), however, leaf size is a poor criterion on which to separate genera and they included similarly large Cup to 100 mm wide) leaves within Taeniopteris. This is supported by our observation that T. taeniopteroides from both Hope Bay and Botany Bay shows a gradation in size between the smallest and largest leaves. Furthermore, the vein density along the leaf margin remains constant except in the smallest leaves, a pattern that compares well with measurements made on lea¯ets of the living cycad genus Zamia Cby PMR at the Botanical Institute, Universidade de SaÄo Paulo). Giddy C1974), Newell C1989), and Jones C1993) have shown that environment can have a signi®cant in¯uence on lea¯et size and form in living cycads and, without implying that it is a cycad, it seems likely that it had a similar effect on T. taeniopteroides. The large range in leaf width, vein density and degree of vein bifurcation in T. taeniopteroides makes it similar to many other species that have been described from localities world-wide, with ages ranging from Triassic to Cretaceous Csee synonymy). However, without information about the range of variation in the leaves from these other localities, it is impossible to be certain that they are conspeci®c. Consequently, they have only been included within the synonymy with a question mark.

Taeniopteris sp.

Plate 16, ®gures 1±2; Text-®gure 5E ?1944 Taeniopteris daintreei McCoy; Frenguelli, pl. 1, ®gs 4±5; pl. 2, ®gs 1±4. ?1976 Taeniopteris daintreei McCoy; Blaschke and Grant-Mackie, ®gs 2±4.

E X P L A N A T I O N O F P L A T E 15 Figs 1±4. Taeniopteris taeniopteroides CHalle) comb. nov. 1, D34.9; wide leaf fragment showing venation; ´ 1. 2, 8093; leaf fragment showing attachment to petiole and general leaf morphology; ´ 1. 3, 8056; apical portion of leaf showing venation; ´ 1´5. 4, D.39.21; small complete leaf showing features seen in the larger incomplete ones; ´ 1´5. All specimens from Hope Bay.

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TEXT-FIG. 5. A±D, Taeniopteris taeniopteroides CHalle) comb. nov. A, MF1ACa); B, MF1ACd); C, MF4A; D, 8982.2B. E, Taeniopteris sp.; D.9029. A±C from Hope Bay, D±E from Botany Bay. Upper scale bar corresponds to A±B, lower scale bar to C±E.

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?1976 Taeniopteris vittata Brongniart; Maheshwari and Singh Cnon Brongniart), pl. 2, ®gs 9, 12. ?1976 Taeniopteris spatulata McClelland; Maheshwari and Singh, pl. 2, ®g. 13; text-®g. 5. ?1980 Taeniopteris sp. Arrondo and Petriella, pl. 3, ®g. e. ?1981 Taeniopteris sp. Baldoni and Ramos, pl. 1, ®g. 3; pl. 2, ®gs 5±6. ?1981 Taeniopteris spatulata; Bose and Banerji, pl. 1, ®gs 1, 6; pl. 5, ®gs 28±29; text-®gs 1A±F, 9B. ?1984 Taeniopteris cf. spatulata; Bose and Banerji, text-®g. 59A±C. ?1988 Taeniopteris spatulata; Sengupta, pl. 7, ®g. 20.

Material. Botany Bay: D.8990A, D.9029, D.9038A.

Description. Leaf long and narrow, simple; complete leaves unknown. Leaves up to 50 mm long, margins entire, parallel to 10±15 mm from leaf apex, then converging. Apex acute, leaf bases not preserved. Leaf width 5´5±8 mm, rachis width 0´7±2 mm. Lamina attached laterally to rachis. Ratio of leaf width to rachis width 3´6±10. Lateral veins simple or forking, parallel, persisting to margins. Veins typically forking within 1 mm from rachis, occasionally forking at varying distance towards margins. Lateral veins arising from rachis Cin middle portion of leaf) at c. 75±908. Angle decreasing towards leaf margins; from 65±908, typically 65±808, at two-thirds of distance from rachis to margins. Vein density near rachis 15±40 per cm, typically 20±30 per cm. Vein density near margins 16±50 per cm, typically 25±40 per cm.

Remarks. These leaf fragments, which only occur at Botany Bay, differ from T. taeniopteroides in being narrower, more parallel-sided, and having a more acute apex CText-®g. 5). Even those examples of T. taeniopteroides which come near in size to those included here Ce.g. D.39.21) are clearly different in being more tapered and having an obtuse apex. These specimens are very similar macroscopically to Nipaniophyllum raoi Sahni Ce.g. Vishnu-Mittre 1957), which is thought to be pentoxylalean foliage CHarris 1962; Sharma 1969; Bose et al. 1985). However, the only other specimens from Botany Bay which could possibly belong to the Pentoxylales are structures that are super®cially similar to the female cone, Carnoconites, and these are more likely to be Equisetum cone fragments Csee earlier description and discussion). In the absence of any concrete evidence of anatomy or reproductive structures, we have assigned these Botany Bay leaves to the noncommittal form-genus Taeniopteris, as have palaeobotanists working with similar material from other Mesozoic Gondwanan ¯oras Ce.g. Douglas 1969; Blaschke and Grant-Mackie 1976; Drinnan and Chambers 1985).

INDETERMINATE Cycadophyte scale leaves Remarks. Both cycads and bennettites produced small scale leaves, which are indistinguishable without evidence from cuticles: Deltolepis and Cycadolepis, respectively CHarris 1964, 1969). Two distinct types of such cycadophytic scale-like leaves have been found at Hope Bay and Botany Bay but, as they are associated with normal fronds that could belong to either the cycads or bennettites, they are not formally named here.

Cycadophyte scale leaf type A Plate 16, ®gure 3 }1913 Cycadolepis sp. Halle, pl. 6, ®g. 15. }1989 Cycadolepis sp. Gee, pl. 8, ®g. 63.

Material. Hope Bay: 8009.

Description. Scale leaf fragment; elongate, cuneate, 38´5 mm long and up to 28 mm wide, tapering from base to apex. Surface covered with ®ne longitudinal striations, diverging from basal region, ending at margins and apex. Leaf apex acute, leaf base unknown. Margins entire, rimmed with ®ne hairs. Length of hairs increasing towards leaf apex; c. 2´5±3´5 mm long in basal region, 5´5±8 mm long near apex. Hairs separate, tapering from their bases to acute apices; c. 10±20 hairs per cm.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:07 ALDEN 54 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Remarks. A very similar specimen from Hope Bay to that ®gured here was assigned by Halle C1913) and Gee C1989) to Cycadolepis sp. Neither of the specimens was found in close association with cycadophyte foliage CGee 1989; this study).

Cycadophyte scale leaf type B Plate 16, ®gure 4 Material. Botany Bay: D.8962.3A, D.8963.3A, D.8963.10B.

Description. Ovate scale leaf, c. 11±15´5 mm long. Maximum width Cincluding marginal hairs) 17±23 mm. Surface covered with ®ne longitudinal striations, diverging from basal region, ending at margins and apex. Leaf apex obtuse, rounded. Margins entire, rimmed with coarse hairs. Length of hairs near-constant along margins; c. 1±2´5 mm long. Hairs separate, tapering from their bases to acute apices; c. 10±20 hairs per cm.

Remarks. These Botany Bay specimens mainly differ from those from Hope Bay in being broadly ovate and having an obtuse apex. Additionally, the scale hairs of the Botany Bay specimens are typically shorter and of more constant length along the scale leaf margins than those from Hope Bay. One of the Botany Bay specimens CD.8962.3A) was closely associated with Pseudoctenis? ensiformis, but the evidence is far from conclusive that they belonged to the same biological species.

Class PINOPSIDA Order PINALES Remarks. Florin C1940, p. 31) had considered the Hope Bay conifers to be related to extant Araucaria, Dacrydium and Podocarpus, believing the ¯ora to be of `decidedly southern composition'. Townrow C1967b) suggested that Pagiophyllum feistmantelii may be closely related to Araucaria. However, as Hope Bay and Botany Bay coniferous shoots are so fragmentary and lack epidermal evidence, we have followed Halle C1913) and Gee C1989) in assigning them to the form-genera Brachyphyllum, Pagiophyllum and Elatocladus. These are morphogenera of the Coniferales, which cannot be assigned to a particular family CHarris 1979). The only coniferous fossils in these ¯oras which can be assigned to a `natural' family are the araucariacean cone scales.

Morphogenus BRACHYPHYLLUM Brongniart emend. Harris, 1979. Type. Brachyphyllum mamillare Brongniart ex Lindley and Hutton, as designated by Harris C1979).

Brachyphyllum sp. Plate 17, ®gure 3 }1913 Brachyphyllum sp. Halle, pl. 8, ®gs 42, 42a; pl. 9, ®gs 14±16. }1989 Brachyphyllum sp. Gee, pl. 8, ®g. 69.

Material. Hope Bay: D.32.16, 5800, 8168.

E X P L A N A T I O N O F P L A T E 16 Figs 1±2. Taeniopteris sp., Botany Bay. 1, D.8990A; leaf fragment showing acute apex; 2, D.9029; leaf fragments showing venation. Both ´ 2´2. Fig. 3. Cycadophyte scale leaf type A, 8009, Hope Bay; ´ 2. Fig. 4. Cycadophyte scale leaf type B, D.8962.3A, Botany Bay; ´ 4.

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Description. Fragments of homophyllous shoots, occasionally branching. Main shoots up to 40 mm long, 1´5±3´0 mm wide. Lateral shoots up to 32 mm long, c. 2 mm wide. Leaves arranged in a helix, touching or up to c. 0´1 mm apart. Leaves closely appressed to, or projecting slightly from, shoot axis. Compressed leaves appearing cuneate, keeled, arising from rhomboidal basal cushion. Leaf margins entire, converging to acute or subobtuse apex. Leaf length 0´5±3´0 mm, basal width 0´5±2´0 mm. Ratio of leaf length to basal width 1±1´8, typically c. 1±1´3.

Remarks. The new material provides little additional information to that given by Halle C1913) and Gee C1989). The shoots differ from those of the other coniferous species at Hope Bay and Botany Bay in the low length to width ratios of their leaves, which are closely appressed to the shoot axis. Gee C1989) compared her Brachyphyllum sp. with Allocladus cribbii Townrow, 1967b. Townrow had included some of the Hope Bay material within his new species but, as correctly pointed out by Gee C1989), the leaves of the Hope Bay shoots are closely appressed to the axis, not free as in A. cribbii. Gee C1989) also compared the Hope Bay specimens with Brachyphyllum rhombicum, originally described from the Madras, South Rewah, Jabalpur and Rajmahal ¯oras of India Creferences cited by Gee 1989; also Sengupta 1988). The Hope Bay specimens are indeed similar to B. rhombicum in that they have small rhombic leaves that are appressed to the shoot axis. However, leaf length in the Hope Bay specimens is equal to or slightly greater than the basal width, and the leaves are strongly keeled, whereas those of B. rhombicum are greater in width than in length and are unkeeled. The Hope Bay specimens are also similar to some of those described from the Middle Jurassic of Yorkshire by Harris C1979) as Brachyphyllum mamillare. As pointed out by Halle C1913, p. 80), in the absence of cuticles or of measurements of leaf parastichies, any comparison of these rare Antarctic specimens with those from other regions is of little value. It is even possible that they were originally part of one of the other coniferous species described from Hope Bay and Botany Bay. In the absence of well-preserved material, further collecting is necessary to seek intermediate forms which could test this.

Morphogenus PAGIOPHYLLUM Heer emend. Harris, 1979 Type. Pagiophyllum cirinicum CSaporta) Heer, 1881.

Pagiophyllum cf. crassifolium Schenk 1871 Plate 17, ®gures 6±7 }1913 Pagiophyllum cfr. crassifolium Schenk; Halle, pl. 8, ®g. 11.

Material. Botany Bay: D.8939B, D.9049A.

Description. Unbranched shoot fragments, up to 24 mm long, c. 1´5 mm wide. Leaves arranged in helix, separate, arising at 50±658, apices directed towards shoot apex. Leaves falcate, lanceolate; acroscopic margin with marked basal expansion. Acroscopic margin concave beyond basal expansion, basiscopic margin convex. Leaf length 3´5±5´0 mm, basal width c. 1´5±2´0 mm. Ratio of leaf length to basal width c. 2´3±2´8.

E X P L A N A T I O N O F P L A T E 17 Figs 1±2. Araucarites cf. cutchensis Feistmantel, Hope Bay. 1, D.32.11; cone scale showing seed scar and apical extension. 2, D.6.3; cone scale showing seed scar and apparently lacking apical extension. Both ´ 2. Fig. 3. Brachyphyllum sp., D.32.16, Hope Bay; shoot fragment; ´ 2´5. Figs 4±5. Pagiophyllum feistmantelii Halle, Botany Bay. 4, D.9005.6B; main shoot C1) and lateral shoot C2) showing different leaf insertion styles. 5, D.9002.6B; fragment of main shoot showing leaf morphology and insertion style. Both ´ 2. Figs 6±7. Pagiophyllum cf. crassifolium Schenk, D.8939B, Botany Bay; 6, shoot fragment; ´ 2; 7, close-up showing leaf morphology and insertion; ´ 5.

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Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:07 ALDEN 58 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Remarks. The two Botany Bay specimens described here are closely similar to the Hope Bay specimens described by Halle C1913) as Pagiophyllum cfr. crassifolium. Gee C1989, p. 203) rejected Halle's species because it was based on insuf®cient material. However, the pronounced basal expansion of the acroscopic margin and the lanceolate form of the leaves distinguish them from the other conifer species at Hope Bay and Botany Bay, so we have opted to retain Halle's designation. As Halle C1913, p. 75) commented, Pagiophyllum crassifolium is known from the Wealden ¯ora of England. However, the Hope Bay and Botany Bay specimens are also similar to Elatides thomasii, Pagiophyllum kurrii and Pagiophyllum insigne from the Middle Jurassic of Yorkshire CHarris 1979). In the absence of more complete material and/or microscopic details, the specimens from Hope Bay and Botany Bay are retained within Pagiophyllum cf. crassifolium, whilst noting that they also resemble several other species and are not age-diagnostic.

Pagiophyllum feistmantelii Halle emend. Townrow, 1967b Plate 17, ®gures 4±5 T1879 Pagiophyllum peregrinum Schimper; Feistmantel Cnon Schimper), pl. 12, ®gs 3, 9. *1913 Pagiophyllum Feistmantelii Halle, pl. 9, ®gs 17±17b; text ®g. 17a±d. }1913 Pagiophyllum sp. Halle, pl. 8, ®g. 41; pl. 9, ®g. 6. 1963 Pagiophyllum Feistmantelii Halle; Bonetti, pl. 7, ®g. 3. 1967b Pagiophyllum feistmantelii Halle; Townrow, pl. 1, ®gs C, F; text-®gs 1G, 2F±G, 7C±D, 8A±B Cother ®gures are of cuticles). }1989 Pagiophyllum feistmantelii Halle; Gee, pl. 8, ®g. 72b. }1989 Pagiophyllum sp. B; Gee, pl. 8, ®g. 68b. See Townrow C1967b) for other synonyms.

Lectotype. Specimen ®gured by Feistmantel C1879, pl. 12, ®g. 3), now stored in the collections of the Geological Survey of India, Calcutta. Designated by Townrow C1967b). Originated from the ?Middle Jurassic of Vemavaram, near Madras, India.

Material. Hope Bay: 8143A. Botany Bay: D.9002.6B, D.9002.9A, D.9005.6B.

Description. Main shoots occasionally branching, up to 76 mm long and 4´5 mm wide Cexcluding divergent leaves). Leaves helically arranged on main shoot, leaf cushions rhomboidal, c. 2´5 ´ 2 mm to 3 ´ 2´5 mm. Leaves arise at c. 50±908 on main shoot, cuneate, margins converging from leaf base to acute apex. Leaf apices typically directed towards base of main shoot Cacroscopic margin convex, basiscopic margin concave or straight). Occasionally, leaf apices directed towards shoot apex Cbasiscopic margin convex, acroscopic margin concave or straight), or at 908 to shoot axis Cboth margins convex). Leaves c. 3´5±4´0 mm long, up to c. 2 mm wide. Ratio of leaf length to width 2±2´3. Lateral shoots arise from main shoot at 55±658, up to 42 mm long and 4 mm wide Cincluding divergent leaves). Leaves arise laterally on shoot, basal cushions not seen. Leaves up to c. 0´5 mm apart on shoot axis, arising at 50±808, cuneate, margins converging from leaf base to acute apex. Leaf apices typically directed towards shoot apex Cbasiscopic margin convex, acroscopic margin concave or straight). Occasionally, leaf apices directed towards base of shoot Cacroscopic margin convex, basiscopic margin concave or straight), or at 908 to shoot axis Cboth margins convex). Leaves c. 1´5±2´5 mm long, up to c. 2 mm wide. Ratio of leaf length to width 1´1±1´3. Remarks. Pagiophyllum feistmantelii was originally described from Hope Bay CHalle 1913), but has since been recorded from Argentina, Australia and India Ce.g. Walkom 1917; Sahni 1928; Frenguelli 1949; Bonetti 1963; Townrow 1967b; Herbst and Anzotegui 1968). Based on the new material from Hope Bay and Botany Bay, a more complete description is provided here, although microscopic details are still unknown. A notable feature is that the leaves are arranged differently on the main and lateral shoots. Leaves on the main shoot have bases that touch; the leaves are arranged helically, with their apices typically directed towards the main shoot base. In contrast, leaves on the lateral shoot are attached laterally, and their bases are up to approximately 0´5mm apart, with their apices typically directed towards the lateral shoot apex. Additionally, leaves on the main shoot have a greater leaf length to maximum width ratio than those on the lateral shoot.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:07 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 59 One specimen from Botany Bay CD.9005.6B) comprises a main shoot segment bearing lateral shoots. The main shoot is identical to those described from Hope Bay as Pagiophyllum feistmantelii by Halle C1913) and Gee C1989). However, the lateral shoots are closely similar to two detached shoots assigned to distinct species of Pagiophyllum by Halle C1913), subsequently combined as Pagiophyllum sp. B CGee 1989). Consequently, these shoots are assigned here to Pagiophyllum feistmantelii. Townrow C1967b) described the microscopic as well as macroscopic characters of P. feistmantelii, but it is still not assignable at the family level. He considered it to be similar to extant Araucaria but, in the absence of evidence of reproductive structures, it is best to retain it within the form-genus Pagiophyllum.

Pagiophyllum cf. feistmantelii Halle emend. Townrow, 1967b Pl. 18, ®gures 1±2 Material. Hope Bay: D.34.6 Cpart and counterpart). Description. A single unbranched shoot, 92´5 mm long, up to 2 mm wide Cwidth decreasing only slightly towards shoot apex). Leaves arise laterally, subopposite, occasionally detached from shoot axis, basal cushions not seen. Leaves separate, c. 2 mm apart near base of shoot, decreasing to c. 0´5 mm near shoot apex, arising at 60±708. Leaves cuneate, margins converging gradually from leaf base to acute apex. Leaf apices typically directed towards shoot base Cacroscopic margin convex, basiscopic margin concave or straight). Occasionally, leaf apices directed towards shoot apex Cbasiscopic margin convex, acroscopic margin concave or straight), or at 908 to shoot axis Cboth margins convex). Leaves c. 4±5 mm long, up to 3´0±3´5 mm wide. Ratio of leaf length to width 1´2±1´6.

Remarks. A single shoot from Hope Bay, preserved as a part and counterpart, bears most resemblance to lateral shoots of Pagiophyllum feistmantelii in leaf shape, attachment to the shoot, orientation of the leaf apex, and the ratio of leaf length to maximum width. However, the leaves of this specimen are almost 2±3 times larger than those seen on lateral shoots of P. feistmantelii, and are nearer in size to leaves on the main shoot of this species. Additionally, leaf apices on lateral shoots of P. feistmantelii are typically directed towards the lateral shoot apex, whereas on this specimen they are typically directed towards the shoot base. This is more similar to the leaf apex orientation seen on the main shoots of P. feistmantelii. Because of these differences, the specimen has been assigned to P. feistmantelii with a `cf.'.

Pagiophyllum sp. Plate 18, ®gures 3±4 }1913 Sphenolepidium? Oregonense Ward; Halle, pl. 9, ®gs 5, 9±11, 13. }1913 Conites? sp. Halle, pl. 9, ®gs 12, 12a. p}1913 Schizolepidella gracilis Halle, text-®g. 19a Cnon pl. 9, ®gs 18±21). }1989 Pagiophyllum sp. A Gee, pl. 8, ®gs 70, 71.

Material. Hope Bay: 5624Ca±b), 5630 Cpart and c/part), 8027, 8035, 8056, 8167, D.13.10 Cpart and c/part). Botany Bay: D.8913.6, D.8958.6A, D.8958.19A, D.9005.9A, D.9005.10A, D.9008B, D.9044A.

Description. See Gee C1989, p. 198).

Remarks. Specimens from Hope Bay described as Sphenolepidium? oregonense by Halle C1913) were assigned to Pagiophyllum by Gee C1989), a view with which we concur. The new material provides no additional information other than that the species is also present at Botany Bay. Some poorly preserved shoots, which we assign to Pagiophyllum sp., bear a slight resemblance to Schizolepidella gracilis, as described by Halle C1913) and Gee C1989). All of the specimens assigned by Halle and Gee to S. gracilis may in fact be merely incomplete shoots of Pagiophyllum sp. but their preservation is too poor to be certain.

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Morphogenus ELATOCLADUS Halle emend. Harris, 1979

Type. Elatocladus heterophylla Halle, 1913.

Remarks. Halle C1913, p. 83) erected Elatocladus, for `sterile coniferous branches of the radial or the dorsiventral type, which do not show any characters that permit them to be included in one of the genera instituted for more peculiar forms'. Harris C1979, p. 104) offered the following emended diagnosis: `fossil conifer shoot bearing elongated, dorsiventrally ¯attened leaves with a single vein. Leaves divergent from stem'. This has been adopted here.

Elatocladus confertus COldham and Morris) Halle, 1913 Plate 18, ®gures 5±6; Plate 19, ®gures 1±2 *1862 Cunninghamites conferta Oldham and Morris, p. 86, pl. 8, ®gs 28±40. }1913 Elatocladus heterophylla Halle, pl. 8, ®gs 12±14, 17±25; text-®g. 18a±b. }§1913 Elatocladus conferta COldham and Morris) Halle, pl. 8, ®gs 26±40. }1913 Elatocladus jabalpurensis CFeistmantel) Halle, pl. 9, ®gs 8, 8a. }1913 Elatocladus sp. Halle, pl. 9, ®gs 7±7b. 1949 Palissya conferta COldham and Morris) Frenguelli, p. 21 Cnote only). 1949 Palissya jabalpurensis; Frenguelli, p. 21 Cnote only). 1963 Elatocladus conferta COldham and Morris) Halle; Bonetti, pl. 7, ®g. 1. 1976 Elatocladus conferta COldham and Morris) Halle; Maheshwari and Singh, pl. 2, ®gs 14±15. 1980 Elatocladus conferta COldham and Morris) Halle; Arrondo and Petriella, pl. 2, ®g. h. 1981 cfA Elatocladus conferta COldham and Morris) Halle; Jefferson, pl. 4.13, ®gs 4±6. 1984 Elatocladus confertus COldham and Morris) Halle; Bose and Banerji, text-®g. 50A±D. 1984 Elatocladus jabalpurensis; Bose and Banerji, text ®gs 50I, 51H±J. }1989 Elatocladus confertus COldham and Morris) Halle; Gee, pl. 8, ®g. 75. }1989 Elatocladus heterophyllus Halle; Gee, pl. 8, ®gs 73±74. }1989 Elatocladus jabalpurensis; Gee, p. 202 Cdescribed but not ®gured). See Gee C1989) for other synonyms and closely-similar specimens.

Syntypes. The specimens illustrated by Oldham and Morris C1862). Their current location is unknown, so we are unwilling here to designate one of them as lectotype.

Material. Hope Bay: 5917, 8008Cb), 8014, 8025, 8109, V.63422. Botany Bay: D.8873, D.8908.3/bB, D.8937.8A, D.8937.10B, D.8938.1B, D.8944.18B, D.8952.1B, D.8952.6B, D.8953.10B, D.8953.14A, D.8958.10A, D.9002.7A, D.9005.3A, D.9007.3A, D.208.1.

Description. Main shoots typically branched; bearing intermediate and ultimate shoots in the lower and central regions, and lateral shoots in the apical region. Main shoots up to 149 mm long, 2´5 mm wide. Intermediate shoots up to 61 mm long, 1 mm wide; ultimate shoots up to 24 mm long, 0´5 mm wide. Intermediate shoots alternate on main shoot, becoming subopposite then opposite distally, arising at 19±458. Ultimate shoots alternate on intermediate shoot, arising at 34±408.

E X P L A N A T I O N O F P L A T E 18 Figs 1±2. Pagiophyllum cf. feistmantelii Halle, D.34.6; Hope Bay; 1, shoot fragment showing leaf morphology and insertion; ´ 1; 2, detail of counterpart; ´ 2´5. Figs 3±4. Pagiophyllum sp., D.9005.9A, Botany Bay; 3, shoot fragment showing leaf morphology and insertion; ´ 5; 4, detail of leaf morphology; ´ 3´5. Figs 5±6. Elatocladus confertus COldham and Morris) Halle, Hope Bay. 5, 8008Cb); main shoot fragment bearing lateral shoots. 6, 8025; apical region of main shoot. Both ´ 1´5.

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Leaves arranged in a helix on shoots, leaf attachment variable; leaves adpressed to shoot axis, or diverging at varying angles. Leaf margins entire, leaf shape variable; divergent leaves either long and linear Cdirected towards shoot apex), or long and narrowly ovate Cdirected apically, or recurved slightly towards base of shoot). Leaves up to 11 mm long, 1´5 mm wide. Ratio of leaf length to maximum width 2±14. Leaf apices acute to obtuse. Neighbouring leaves touching or up to 2 mm apart. Leaves arise from main shoot at 10±858, from intermediate shoot at 15±808, and from ultimate shoot at 35±858. Apical region of leaves on main shoot at 20±1108 to main shoot axis. Apical region of intermediate shoot leaves at 30±958 to intermediate shoot axis, apices of ultimate shoot leaves at c. 908 to ultimate shoot axis. Venation only occasionally preserved; one central vein seen, persisting nearly to leaf apex.

Remarks. Halle C1913) recognised four species of Elatocladus in the Hope Bay ¯ora. Gee C1989) maintained three of these species but rejected E. sp. on the grounds of there being `insuf®cient material'. Based on the new material from Hope Bay and Botany Bay, all of these species are assigned to Elatocladus confertus. Gee C1989) distinguished E. heterophyllus from the other Elatocladus species in the Hope Bay ¯ora mainly because it has heterophyllous shoots, with leaves varying in form between thick and closely appressed, and thin and widely spread. Gee C1989, p. 196) described E. confertus as having leaves that were re¯exed near their apices, whereas E. jabalpurensis leaves were more or less straight from the shoot axis. As she pointed out, however, leaf heteromorphism is not unusual in extant conifers; a full-sized tree can exhibit juvenile and adult, as well as intermediate, types of leaf. Such heteromorphism is shown by several of the new Elatocladus specimens, which have different forms of leaf attached to the same shoot, and one CPl. 19, ®gs 1±2) has shoots and leaves characteristic of all of the previously described species. Some of the variation seen in leaf orientation may also have been due to differing degrees of distortion during burial. All of the available evidence seems to point to just a single heterophyllous Elatocladus species being present at Hope Bay and Botany Bay, for which E. confertus has nomenclatural priority. Maheshwari and Singh C1976) described heterophyllous conifer shoots from the Pariwar Formation, India, as E. confertus. Gee C1989) transferred these to E. heterophyllus, believing that E. confertus was homophyllous. As pointed out above, however, this latter view is incorrect and we accept Maheshwari and Singh's original identi®cation.

Family ARAUCARIACEAE Henkel and Hochstetter, 1865 Genus ARAUCARITES Presl, in Sternberg 1838

Type. Araucarites goeppertii Presl, in Sternberg 1838.

Remarks. See Cleal and Rees C2003) for a discussion of this morphogenus.

Araucarites cf. cutchensis Feistmantel, 1877 Plate 17, ®gures 1±2 }1913 Araucarites cutchensis Feistmantel; Halle, pl. 8, ®gs 3±10; text-®g. 16a±b. 1981 cf. Araucarites cutchensis CFeistmantel); Jefferson, pl. 4.17, ®gs 2±3. }1989 Araucaria antarctica Gee, pl. 8, ®gs 64±68a, 72a.

E X P L A N A T I O N O F P L A T E 19 Figs 1±2. Elatocladus confertus COldham and Morris) Halle. 1, V.63422, Hope Bay; fragment of main shoot bearing intermediate and ultimate shoots in the lower and central regions, and lateral shoots in the apical region; note the variation in leaf morphology and insertion; ´ 1. 2, D.208.1, Botany Bay; fragment of main shoot bearing lateral shoots; ´ 2. Fig. 3. Leaf of unknown af®nity, D.39.23, Hope Bay; leaf fragment showing morphology and venation; ´ 0´75.

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Material. Hope Bay: D.6.2, D.6.3, D.21.4, D.32.11, 5622, 8001.

Description. Detached bracts, cuneate, margins diverging from base to widest point Cc. 80 per cent of distance from base to apex), converging distally to a near-horizontal margin. Bract 10±19´5 mm long, 3´5±5 mm wide at base, expanding to a maximum width of 8´5±18´5 mm. Ratio of bract length to maximum width 0´9±1´2. Apex cuneate, pointed at tip, arising at 908 from centre of near-horizontal margin of scale. Apex length 1´1±2´6 mm, basal width 1´2±3´5 mm. Ratio of apex length to basal width 0´7±1´1. Seed scar ovate, situated in central region of scale, 8±14´1 mm long, up to 3´7±7 mm wide. Ratio of seed scar length to maximum width 2´0±2´5. Ratio of bract length to seed scar length 1´2±1´4, ratio of maximum bract width to maximum seed scar width 2´1±3´3.

Remarks. Species of fossil araucarian cone bracts are distinguished Cin the absence of cuticle) by their size and the proportions of their component parts, although there is considerable variation in these features within individual cones CHarris 1979). The cuticle is very helpful but has been described in less than half of the species. The Hope Bay specimens lack microscopic details and were found only as detached bracts of varying size and shape. Halle C1913, p. 73) assigned the original Hope Bay specimens to Araucarites cutchensis, some of which he described as being ligulate. According to Bose and Maheshwari C1973), A. cutchensis lacks a ligule, so Gee C1989) assigned the Antarctic specimens to a new species CAraucaria antarctica). However, Pant and Srivastava C1968) had earlier shown that A. cutchensis does in fact have a ligule and that those examples that are apparently eligulate are either poorly preserved or are preserved showing their lower side. The presence of a ligule in the Hope Bay specimens cannot, therefore, be used to justify assigning them to a separate species, although it is strong evidence that they are araucariacean cone bracts. There are several other species that are morphologically similar to the Hope Bay specimens, but which cannot be separated without cuticles: A. minutus CBose and Maheshwari 1973; Bose and Banerji 1984), A. janaianus CBose and Banerji 1984), A. chilensis CBaldoni 1981b) and A. sp. CHerbst 1966). However, we have assigned them to Araucarites cf. cutchensis, this being the oldest of the available names.

Class unknown Remarks. Included here are remains of foliage of plants of unknown af®nities. There is no unequivocal proof, but foliage of this type normally occurs in gymnospermous seed plants, and we have assumed the same. Such plants have often been included within a taxon called Pteridospermopsida, i.e. gymnosper- mous seed plants Cother than the cycads, bennettites and related plants) with compound leaves. However, this is an outdated `grade-group' with little taxonomic justi®cation and has not been used here.

Morphogenus PACHYPTERIS Brongniart emend. Harris, 1964 Type. Pachypteris lanceolata Brongniart, 1829.

Remarks. Harris C1964) argued that Pachypteris was probably the foliage of a corystospermacean plant, based on the repeated association of P. papillosa CThomas and Bose) Harris and the pollen organ Pteroma thomasii Harris in the Jurassic of Yorkshire. However, he admitted that the evidence was not conclusive and that he had no direct evidence of the ovulate organs Calthough he compared the structure of Pteroma with the corystospermacean ovulate organs Pteruchus). As there is no good evidence of the reproductive

E X P L A N A T I O N O F P L A T E 20 Figs 1±5. Pachypteris indica COldham and Morris) Bose and Roy. 1, V.63744, Hope Bay; frond segment; ´ 1´5. 2±5 Botany Bay. 2, V.63761; frond segment; ´ 2. 3, V.63760; frond segment bearing fused pinnules; ´ 1´5. 4, V.63755; impression surfaces of pinnules and pinna rachis showing traces of stomata and cell outlines; ´ 10. 5, V.63755; detail of stomata and cell outlines on impression surface of the upper right-hand pinnule in 4; ´ 70.

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Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:08 ALDEN 66 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 structures of the Southern Hemisphere species Pachypteris indica, which occurs at Botany Bay and Hope Bay, we have included it under incertae sedis.

Pachypteris indica COldham and Morris) Bose and Roy, 1968 Plate 20, ®gures 1±5 *1862 Taxodites? indicus Oldham and Morris, pl. 33, ®gs 5±6. }1913 Sphenopteris CRuffordia?) Goepperti Halle, pl. 3, ®g. 9. 1956 Sphenopteris bagualensis MeneÂndez, pl. 1; pl. 2, ®gs 1±2; text-®g. 1. §1968 Pachypteris indica COldham and Morris) Bose and Roy, p. 2, text-®gs 1±4, 5a; pl. 1, ®gs 3±5, 7; pl. 2, ®gs 10±14; pl. 3, ®gs 15±16, 19±20. 1984 Pachypteris indica COldham and Morris) Bose and Roy; Bose and Banerji, pl. 8, ®gs 1±8; pl. 9, ®gs 1, 5, 7±9; pl. 10, ®gs 5±6; pl. 11, ®gs 8±9; text-®gs 17, 18A±F, 19A±F, 20A±J, 21A±D. }1989 Sphenopteris bagualensis MeneÂndez; Gee, pl. 4, ®g. 30. See Bose and Banerji C1984) for other synonyms.

Holotype. Geological Survey of India, Calcutta, specimen number 4909 CBose and Roy 1968, pl. 2, ®g. 13). From the Lower Cretaceous Jabalpur Group, Sehora, Sher River, India.

Material. Hope Bay: V.63744. Botany Bay: V.63426, V.63745 to V.63762.

Description. Frond bipinnate, lamina coriaceous. Extent of frond unknown, up to at least 73 mm long and 51 mm wide. Frond rachis 1´5±3´0 mm wide. Pinnae alternate to subopposite on rachis, arising at 20±558, typically c. 458; pinna bases decurrent. Pinnae 13±60 mm long Cusually 25±30 mm), spaced 7±12 mm apart on frond rachis. Pinna rachis 1´0±1´5 mm wide. Pinnules arising from upper surface of pinna rachis, decurrent at their bases. Pinnules typically alternate, occasionally subopposite or opposite, arising at 10±458. Lowermost pinnule arising from basiscopic side of rachis. Pinnules 7±18 mm long, 1´5±2´5 mm maximum width. Pinnule margins diverge for c. 65±85 per cent of distance from base to apex, then converge. Pinnule apices acute to obtuse, occasionally with small mucronate tip. Neighbouring pinnules usually separate, but sometimes in contact along margins. Where neighbouring pinnules are separate, lowermost pinnules on pinna are commonly bi- or trilobed. Fused pinnules form small, rhomboidal, pinnae C13±17 mm long) that are constricted at their bases, with acute or obtuse apices. Venation indistinct; occasionally, one vein seen persisting to pinnule apex. In lobed pinnules, vein bifurcates, each fork persisting to a lobe apex. Cells and stomata visible on impressions of surfaces Cprobably lower) of better- preserved pinnules. Cells rectangular or polygonal, elongated parallel to pinnule margins. Most stomata distributed irregularly, occasionally aligned in rows parallel to pinnule margins. Impression surfaces with stomatal subsidiary cells forming a sunken region Cc. 30±60 mm diameter) around raised central area Cc. 10±20 mm diameter), corresponding to a thickened ring around stomatal pit of actual pinnule surfaces.

Remarks. Hope Bay specimens assigned by Halle C1913) to Sphenopteris CRuffordia?) goeppertii were transferred to Sphenopteris bagualensis by Gee C1989). S. bagualensis was erected by MeneÂndez C1956) for borehole fragments with cuticles from the Middle Jurassic Bajo de los Baguales ¯ora of Argentina. New Hope Bay and Botany Bay specimens now allow a better comparison with S. bagualensis. In particular, one Botany Bay specimen has traces of stomata and cell outlines preserved on impression of some of the pinnules CPl. 20, ®gs 4±5). The stomatal size, shape and distribution on these pinnules is identical to that seen on the specimens described by MeneÂndez C1956, pl. 1, ®gs 2±3). The new Hope Bay and Botany Bay specimens are also very similar macroscopically to S. bagualensis and it is clear that the Antarctic and Argentine specimens are conspeci®c. However, new work has shown that S. bagualensis should be regarded as a super¯uous later synonym of Pachypteris indica. P. indica is known principally from India, although rare specimens have also been described from Australia Cas Pachypteris cf. indica; Tidwell et al. 1987). Most Hope Bay and Botany Bay specimens agree macro- and microscopically with P. indica described from Kachchh, India, by Bose and Banerji C1984, text-®gs 18D±F, 19B, E±F, 20I, 21A±B). The only difference is that a few of the Antarctic specimens have pinnules that are more closely spaced or even fused along their margins compared with the Kachchh material. However, these rare, atypical forms do not preclude the assignment to P. indica.

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Morphogenus KOMLOPTERIS Barbacka, 1994 Type. Komlopteris nordenskioeldii CNathorst) Barbacka.

Remarks. Barbacka C1994) recognised that many of the species assigned to Thinnfeldia Ettingshausen, 1852 were fundamentally different from its type Cwhich was probably a Pachypteris species) in both morphology and epidermal anatomy. Barbacka C1994) therefore proposed the genus Komlopteris for these species. For further comments on this issue, see Cleal and Rees C2003).

Komlopteris indica CFeistmantel) Barbacka, 1994, nov. emend. Plate 21, ®gures 2±4 *1877 Thinnfeldia indica Feistmanel, p. 87, pl. 39, ®g. 1; pl. 46, ®gs 1±2. }1913 Pachypteris dalmatica Kerner; Halle Cnon Kerner), pl. 4, ®gs 23±28, 33, 35. }1913 Thinnfeldia constricta Halle, pl. 4, ®gs 29±32, 34; text-®g. 10a±d. }1943 Pachypteris Hallei Frenguelli, ®g. 4 Crenaming and re®guring of Hope Bay material). ?1986 Thinnfeldia sp. cf. T. indica Feistmantel; Drinnan and Chambers, ®g. 23A±D. 1988 Thinnfeldia indica Fesitmantel; Sengupta, pl. 15, ®g. 39. }1989 Pachypteris hallei Frenguelli; Gee, pl. 4, ®gs 36±37. }1989 Thinnfeldia constricta Halle; Gee, pl. 5, ®gs 44±46. 1994 Komlopteris indica CFeistmantel) Barbacka, p. 348. See Sengupta C1988) for other synonyms.

Lectotype. Geological Survey of India CCalcutta), specimen 4511 Coriginally ®gured by Feistmantel 1877, pl. 39, ®g. 1). Provenance not recorded other than `Rajmahal bed'. Designated by Zeba-Bano et al. C1979).

Material. Hope Bay: 5501, 5502, 5506, 5507, 5689a, 5689b.

Description. Pinnae bearing elongate, decurrent pinnules. Maximum preserved pinna length 88 mm, rachis width 0´5±2´0 mm. Pinnules opposite to alternate on pinna rachis, arising at 20±508, 7´5±20 mm apart. Pinnules 22±40 mm long, maximum width 6±10 mm; maximum width 28±41 per cent of distance from base to apex. Pinnule basiscopic margins decurrent, acroscopic margins typically contracted, occasionally straight. Pinnules elongate, rhomboidal, apices acute. Pinnule margins either entire, undulating, or variably lobed. Lobes 1±3 mm long, basal width 1´5±3´0 mm Csmaller lobes classed as margin undulations). Lobe apices obtuse. Pinnule primary vein strong C0´2±0´5 mm wide at base), extending from pinna rachis to 52±98 per cent of distance from pinnule base to apex. Secondary veins indistinct, diverging from primary vein at 10±208, reaching pinnule margins at 10±408. Secondary veins forking once or twice; ®rst fork occurring in ®rst third of distance from primary vein to margins, second fork in last third. Angle between forks c. 5±108, forks diverging gradually and ending freely at margins. Secondary vein concentration at margins c. 8±15 per cm.

Remarks. Barbacka C1994) transferred this species to Komlopteris. Morphologically, it does not agree completely with the original diagnosis for Komlopteris, the pinnules being a little smaller and sometimes being somewhat incised. However, the cuticular evidence for `Thinnfeldia' indica published by Maheshwari C1986) shows that it has more in common with Komlopteris than Pachytheca, so we have accepted Barbacka's opinion on this. It also avoids the dif®culty that Pachypteris indica is a pre-existing name, so a new name would be required for Feistmantel's species if it were to be transferred to Pachypteris. This species occurs at Hope Bay but not Botany Bay. Included here are Hope Bay specimens that Halle C1913) assigned to a new species Thinnfeldia constricta. Halle C1913) and Gee C1989) regarded T. constricta as being very similar to K. indica from India Csee also Rao 1953), but which differed in details of the venation, pinnule size and attachment to the pinna rachis. However, the new Hope Bay specimens are identical in pinnule shape and size, insertion style and angle on the pinna rachis, as well as in pinna rachis width to a Rajmahal Hills specimen which Sengupta C1988, p. 73) regarded as closely resembling the lectotype of K. indica. The Indian specimen only differs in having pinnule secondary veins

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which diverge at wider angles from the primary vein C25±308, compared with 10±208 in the Hope Bay specimens), and a higher secondary vein concentration at the pinnule margins C14±18 per cm, compared with 8±15 per cm). These differences are too insigni®cant to justify distinguishing the Hope Bay specimens from K. indica. Halle C1913) assigned other Hope Bay specimens to Pachypteris dalmatica. These were subsequently renamed P. hallei by Frenguelli C1943), a change accepted by Gee C1989). According to Gee C1989), these specimens had small pinnules of variable size and shape Cgenerally from 5±10 mm long, but up to 15 mm long and 3 mm wide), attached to pinnae which are at least 49 mm long and 12 mm wide. However, if Gee's description of P. hallei is rewritten so that what she termed pinnae and pinnules are renamed as pinnules and lobes respectively, then it only differs from K. indica in margin style; pinnules of P. hallei are variably lobed, whereas those of K. indica have entire margins. Moreover, one of the new Hope Bay fragments Cspecimen 5689a) has pinnules with entire, undulating, and variably lobed margins all attached to the same pinna. As the specimens assigned to P. hallei/P. dalmatica are otherwise indistinguishable from K. indica there seems little reason for distinguishing them taxonomically.

Morphogenus DICROIDIUM Gothan, 1912 Type. Dicroidium odontopteroides CMorris) Gothan Csyn. Pecopteris odontopteroides Morris, in Strzelecki 1845).

Remarks. Gothan C1912) established this genus for some of the species that had previously been assigned to Thinnfeldia. The main diagnostic character was a basal dichotomy of the frond, whereas those species Gothan regarded as true Thinnfeldia Cnow divided between Pachypteris and Komlopteris) have non- bifurcate fronds. Townrow C1958) complicated the issue by establishing the form-genus Hoegia for two specimens that had been assigned to Dicroidium feistmantelii, but which he regarded as having non-bifurcate fronds CFeistmantel 1879, pls 29±30). However, it is far from certain that these are parts of non-bifurcate fronds and one CFeistmantel 1879, pl. 28) has a curved rachis that could easily represent part of a branch produced by a dichotomy. Townrow C1958) argued that there were differences in the stomatal apparatus and the epidermal structure of the rachises, but these do not seem to demarcate sharply the two groups of species CArchangelsky 1968). We therefore agree with Archangelsky C1968) and do not recognise Hoegia as a distinct form-genus. The distinction of Dicroidium from Thinnfeldia Cnow Pachypteris and Komlopteris) has been discussed frequently. The sole macroscopic character distinguishing them is that the petiole of Thinnfeldia never forks whereas in Dicroidium it usually does CGothan 1912; Frenguelli 1943; Townrow 1958). Where well preserved, a number of microscopic characters also serve to distinguish them CTownrow 1958) but small specimens without microscopic details can be dif®cult to assign. Specimens have tended to be assigned to Dicroidium if they are no younger than early Late Triassic and to Thinnfeldia if they are of late Late Triassic or Early Jurassic age Ce.g. Townrow 1958), a slightly circular line of reasoning. However, Drinnan and Chambers C1986) have described Early Cretaceous examples of Thinnfeldia from the Koonwarra ¯ora of Australia. Thinnfeldia has also been described from the Rajmahal Hills ¯oras Ce.g. Sengupta 1988), whose age is estimated to be anything from Early Jurassic to Early Cretaceous Csee later discussion).

Dicroidium feistmantelii CJohnston) Gothan, 1912 emend. Townrow, 1958 Plate 10, ®gures 1±2 T1879 Thinnfeldia odontopteroides CMorris); Feistmantel Cnon Morris), p. 165, pls 27±29. T1890 Thinnfeldia odontopteroides CMorris); Feistmantel Cnon Morris), p. 101, pls 23±25. *1894 Thinnfeldia Feistmantelli Johnston, p. 175. 1896 Thinnfeldia Feistmantelli Johnston; Johnston, pl. 1, ®g. 2. 1912 Dicroidium Feistmanteli Gothan, p. 78, pl. 16, ®g. 1 Ccopy of part of lectotype). k1914 Dicroidium Feistmanteli CJohnston) Gothan; Antevs, p. 52, pl. 4, ®gs 5±6; pl. 5, ®g. 1 Ccopy of part of lectotype).

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1958 Dicroidium feistmanteli CJohnston) Gothan; Townrow, 39, Text-®g. 2F, 5G±F, 7A±B, 9A±F. 1967a Dicroidium feistmantelii Johnston; Townrow, Fig. 4B.

Lectotype. Specimen ®gured by Feistmantel C1879, pl. 27, ®g. 1), designated by Townrow C1958). It originated from the Hawkesbury Formation, Mount Victoria, New South Wales, Australia.

Material. Botany Bay: V.63763 to V.63765.

Description. Bipinnate frond segments. Frond rachis up to 1´5 mm wide, pinna rachis up to 0´8 mm wide where it arises from the frond. Pinnae alternate, arising at 55±658, c. 6±10 mm apart. Pinnules alternate to subopposite, decurrent on pinna rachis, connected basally by a thin lamina up to 0´5 mm wide. Lowermost pinnule arising on basiscopic side of rachis. Neighbouring pinnules commonly overlapping slightly. Acroscopic margins of pinnules 5´5±6´5 mm apart. Pinnules 6´0±12´5 mm long, 3±7 mm wide. Pinnules merging towards pinna apex. Veins arising on basiscopic side of pinnule at 5±308, 24±30 veins per cm at margins Cmeasured in central region of pinnule). Veins diverging from pinnule base, commonly forking several times at varying distance towards margins, terminating at lateral and apical margins.

Remarks. The fragmentary Botany Bay specimens Ccollected from scree in the lower levels of the measured section) agree macroscopically with Townrow's C1958) emended diagnosis for D. feistmantelii. None shows the characteristic forked rachis but this is probably just because of their fragmentary nature. Closely similar specimens, also not preserving the fork, have been described from Mount Bumstead CEast Antarctica) as D. feistmantelii CTownrow 1967a). The Mount Bumstead ¯ora comes from an isolated boulder of unknown horizon, but it is similar in composition to a nearby ¯ora from Allan Nunatak. Both ¯oras are believed to be of late Middle or early Late Triassic age CTownrow 1967a). The nomenclature of this species has been plagued with problems, due to errors in quoting literature by earlier authors. Some of the problems originated from the way that the syntypes were described and illustrated by Feistmantel C1878±1879). The description and illustration of these specimens was in the last part of Feistmantel's monograph, published in 1879, whereas most subsequent authors have quoted the published date as 1878 Cwhen the earlier parts were published). In this last part, Feistmantel used two parallel numbering-systems for the plates, one continuing from the earlier parts, the other starting afresh from the last part. So, for instance, the illustration of the lectotype of the present species is on what Feistmantel gave as `Tafel IX CXXVII)'. Furthermore, two of the plates illustrating syntypes of this species Cpls 28 and 29) are printed on a single foldout, without any division between them. Some authors have interpreted this as a single plate, normally referred to as plate 11. The confusion that this has caused is exempli®ed by Townrow C1958). He designated as holotype of his new species, Hoegia papillata, the specimen shown in Feistmantel C1878, pl. 11, ®g. 1), whereas from his description he clearly meant Feistmantel C1879, pl. 28, ®g. 1). Another source of confusion is that Feistmantel C1890) later published an English translation of his monograph. This used exactly the same plates but with different numbering and, what is worse, in a different order. Plates 23/24 of Feistmantel C1890) are the same as plates 10/11 C28/29) of Feistmantel C1879), and plate 25 of Feistmantel C1890) is the same as plate 9 C27) of Feistmantel C1879). Johnston C1894) was the ®rst to recognise that the specimens ®gured by Feistmantel as Thinnfeldia odontopteroides were different from the types of that species, representing a more robust frond that originated from a higher stratigraphical level. He therefore proposed transferring them to a new species called Thinnfeldia feistmantelii. Although Johnston did not give the full reference details, it is clear that he was referring to the Feistmantel C1890) monograph. He stated that the new species was based on the specimens on Feistmantel's plates 29±30, but this corresponds to the relevant plates in neither Feistmantel C1890) nor C1879). However, from Johnston's taxonomic analysis, there can be little doubt that he was in fact referring to Feistmantel C1890, pls 23±25). When establishing the new genus Dicroidium, Gothan C1912) stated that Feistmantel's specimens were different from true D. odontopteroides, and referred to them as D. feistmantelii. It has been generally assumed that Gothan was following Johnston in this and, for instance, Townrow C1958) refers to the species as D. feistmantelii CJohnston) Gothan. However, Gothan makes no mention of Johnston's paper

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:08 ALDEN 70 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 and clearly states that it is D. feistmantelii sp. nov. It seems that, quite fortuitously, both he and Johnston independently proposed the same species name for the same taxonomic concept and based on the same types. The only alternative explanation is that Gothan had forgotten that he had read Johnston's paper when making his proposals, which seems even less likely. The attribution of the authorship of this species is therefore somewhat ambiguous but we have continued to use the traditionally accepted form, D. feistmantelii CJohnston) Gothan. Anderson and Anderson C1983) argued that D. feistmantelii is a later taxonomic synonym of D. zuberi CSzajnocha) Archangelsky. However, Archangelsky C1968) distinguished D. feistmantelii by the entire margins of the pinnules, the lower venation density, the thinner cuticle and the lower stomatal density. The Botany Bay specimens are clearly closer to D. feistmantelii than D. zuberi. We realise that our assignment of these specimens to Dicroidium could be taken to infer a Triassic age. However, we are simply applying a `correct' taxonomic approach. The Early Jurassic age assignment for the Hope Bay and Botany Bay ¯oras incorporates other evidence Cdiscussed later).

Morphogenus ARCHANGELSKYA Herbst emend. Rees and Cleal, 1993 Type. Archangelskya protoloxsoma CKurtz) Herbst, 1964b.

Diagnosis. Frond with main rachis which dichotomises at an acute angle, forming two main segments; each segment is up to quadripinnately divided. Segments imparipinnate, with subopposite to alternate pinnae. Pinnules small Cmostly less than 10 mm long), polymorphic, with entire or lobed margins. Pinnule venation consists of midvein, with simple or freely-dichotomising lateral veins. CFrom Rees and Cleal 1993).

Archangelskya furcata CHalle) Herbst emend. Rees and Cleal, 1993 Plate 21, ®gure 1; Plate 22, ®gures 1±4 *}1913 Scleropteris furcata Halle, p. 37, pl. 4, ®gs 3, 10±11, 13±18; text-®g. 9a±b. }1913 Sphenopteris Anderssonii Halle, p. 33, pl. 3, ®g. 10; pl. 4, ®gs 1±2; text-®g. 8a±c. }1913 Sphenopteris Fittoni Seward; Halle, p. 29, pl. 3, ®gs 15±18; text-®g. 7a±c. }1913 Sphenopteris Nauckhof®ana CHeer) Halle, p. 27, pl. 3, ®gs 26, 26a; text-®g. 6a±c. }1913 Scleropteris crassa Halle, p. 36, pl. 3, ®g. 14; pl. 4, ®gs 4±9, 12, 22. }1913 Scleropteris furcata? Halle, pl. 4, ®gs 19, 19a. 1963 Scleropteris furcata Halle; Bonetti, p. 29, pl. 3, ®g. 5. §1964b Archangelskya furcata CHalle) Herbst, p. 121 Cchange of name only). 1968 Archangelskya furcata CHalle) Herbst; Herbst and Anzotegui, p. 186, ®g. 1E±F. }1989 Sphenopteris anderssonii Halle; Gee, p. 171, pl. 3, ®gs 26±28. }1989 Sphenopteris hoppetsvikensis Gee, p. 174, text-®g. 3. }1989 Pachypteris crassa CHalle) Townrow; Gee, p. 178, pl. 4, ®gs 34±35. }1989 Archangelskya furcata CHalle) Herbst; Gee, p. 182, pl. 4, ®gs 38±40. }1993 Archangelskya furcata CHalle) Herbst; Rees and Cleal, p. 98, text-®gs 2±7.

E X P L A N A T I O N O F P L A T E 21 Fig. 1. Archangelskya furcata CHalle) Herbst; V.63694, Botany Bay, frond segment showing secondary pinnae bearing sphenopterid pinnules and tertiary pinnae with scleropterid pinnules; pinnule morphology and venation along the lowermost secondary pinna ranges from scleropterid at the base to sphenopterid near the apex; ´ 3. Figs 2±4. Komlopteris indica CFeistmantel) Barbacka, Hope Bay. 2, 5502; pinna fragment showing basally decurrent pinnules on the pinna rachis; ´ 1´5. 3±4, 5506; 3, pinna fragment showing pinnule morphology and insertion on the pinna rachis; ´ 1; 4, detail, showing primary vein and bifurcating secondary veins; ´ 2.

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REES and CLEAL, Archangelskya, Komlopteris

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Lectotype. Swedish Natural History Museum, Palaeobotanical Section, specimen number S 20083. Designated by Gee C1989).

Material. Twenty-two specimens were listed as being measured in Rees C1990), but the published description CRees and Cleal 1993) is based mainly on the ®ve more complete specimens, V.63693±V.63697.

Description. See Rees and Cleal C1993).

Remarks. The interpretation of this species is based on our earlier analysis of this highly polymorphic foliage CRees and Cleal 1993) and the details need not be repeated here. Suf®ce it to say that this analysis demonstrated that numerous form-genera and -species previously identi®ed from Hope Bay by Halle C1913) and Gee C1989) re¯ect the range of variation in morphology of this species Csee above synonymy). A reconstruction of the whole frond was provided by Rees and Cleal, who were also able to demonstrate the sort of `mini-fronds' that are known from certain Late Palaeozoic lianas such as Mariopteris CBoersma 1972).

Leaf of unknown af®nity Plate 11, ®gure 3 Material. Hope Bay: D.39.23 Cpart and counterpart).

Description. Leaf fragment, 128 mm long Ccomplete extent unknown), 7 mm wide at base. Width near-constant to 55 per cent of distance from base of leaf to apex, margins then converging to apex. Margins entire, apex acute. Veins coarse, near-parallel, simple, 8±10 veins in basal and central regions of leaf, decreasing to four near leaf apex. Central veins persist from base of leaf to apex, lateral veins terminate at margins, at varying distance from base of leaf. Vein density 13±17 per cm.

Remarks. Harris C1964, p. 87, text-®g. 38A±D; pl. 3, ®gs 5±6) described and ®gured a similar specimen Ca cycadophyte from Yorkshire) as Pseudoctenis sp. A. However, the Hope Bay leaf is also similar to coniferophyte specimens assigned to Lindleycladus or Podozamites Ce.g. Harris 1979, and references therein). Without microscopic details, or more complete material showing pinna/leaf attachment to a main axis, the af®nities of this specimen remain unknown.

A G E O F T H E H O P E B A Y A N D B O T A N Y B A Y F L O R A S It has long been recognised that establishing the age of the Hope Bay ¯ora is critical for unravelling the geology of this part of Antarctica Csee reviews in Rees 1990, 1993a, c). However, the age had been based largely on comparisons and correlations of material described by Halle C1913). Although Gee C1989) provided a taxonomic revision of this collection, no new evidence from the ¯ora was available until the studies of Rees C1990, 1993a±d) and Rees and Cleal C1993). Material described herein allows us to provide a complete appraisal of this ¯ora Ca full list of the species recognised is given in Table 2), con®rming an Early Jurassic age. We expand here on the discussions in Rees C1990, 1993a, c) of the most frequently cited

E X P L A N A T I O N O F P L A T E 22 Figs 1±4. Archangelskya furcata CHalle) Herbst. 1±3, V.63693. 1, frond segment; ´ 0´5. 2, detail of apical region of frond segment showing secondary pinnae bearing sphenopterid pinnules; ´ 1´5. 3, detail of secondary pinnae in basal region of frond segment showing tertiary pinnae bearing scleropterid pinnules; ´ 1´5. 4, V.63696; small asymmetrical frond segments with C1) secondary pinnae bearing scleropterid pinnules in the basal and central regions of the segments, and C2) the left hand segment bearing sphenopterid pinnules in its apical region; ´ 1´5. All specimens from Botany Bay.

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TABLE 2. Full list of species recognised in the Hope Bay and Botany Bay ¯oras. Previously described species accepted here, but not present in the new material, are given in parentheses. Order of taxa as in the Systematic Palaeontology section.

Hope Bay Botany Bay

Equisetum laterale X X Goeppertella jeffersonii X Goeppertella woodii X X CGoeppertella herbstii Morel et al.) X Hausmannia papilio X X cf. Matonidium sp. X Coniopteris lobata X X Coniopteris cf. murrayana X Coniopteris sp. A X X Coniopteris sp. B X Todites williamsonii X X Cladophlebis antarctica X X Cladophlebis denticulata X X Cladophlebis oblonga X X CCladophlebis? sp. sensu Halle) X Sphenopteris nordenskjoeldii X Sphenopteris pecten X X Sagenopteris nilssoniana X X Caytonanthus sp. X Ctenis sp. cf. exilis X X Pseudoctenis? ensiformis X X Zamites? antarcticus X X Otozamites? latior X X Otozamites? linearis X X CWilliamsonia pusilla Halle) X CWeltrichia sp. sensu Gee) X Taeniopteris taeniopteroides X X Taeniopteris sp. X Cycadophyte scale leaf type A X Cycadophyte scale leaf type B X Brachyphyllum sp. X X Pagiophyllum cf. crassifolium X X Pagiophyllum feistmantelii X X Pagiophyllum cf. feistmantelii X Pagiophyllum sp. X X CSchizolepidella gracilis Halle) X Elatocladus confertus X X Araucarites cf. cutchensis X X Pachypteris indica X X Komlopteris indica X Dicroidium feistmantelii X Archangelskya furcata X X Leaf of unknown af®nity X CSeed of unknown af®nity Halle) X

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 75 analyses of this problem and those with apparently the most conclusive arguments. Other analyses are similar in nature and were reviewed in more detail by Rees C1990). The ¯ora described from nearby Williams Point, Livingston Island, assigned a Triassic age Ce.g. Lacey and Lucas 1981; Barale et al. 1994), is Late Cretaceous Ce.g. Rees and Smellie 1989; Chapman and Smellie 1982; Poole and Cantrill 2001). Rather than provide a review of this and other Antarctic ¯oras and their ages, we focus here on the stratigraphical evidence pertaining directly to Hope Bay and Botany Bay.

Previous palaeobotanical age assignments Although he did not study the material in any detail, Nathorst C1907) regarded the Hope Bay ¯ora as being closely similar to Jurassic ¯oras of Europe, and having some resemblance to Upper Gondwana Ci.e. late Mesozoic) ¯oras of India. He described it as `Upper Jurassic' in the title of his short paper, but it is not stated in the text. In his more comprehensive study, Halle C1913, p. 98) commented that `the Jurassic age of the Hope Bay ¯ora is evident at the ®rst glance and is con®rmed by a closer comparison with other ¯oras of that epoch'. He compared it with Middle Jurassic ¯oras of Yorkshire, Rhaeto-Liassic ones from elsewhere in Europe, and those of the Upper Gondwana ¯oras of India. At that time, the only South American ¯oras known to Halle were those of mainly Triassic age from Argentina and Chile, and, unsurprisingly, he did not regard these as being contemporaneous with the Hope Bay ¯ora. He assigned a Middle Jurassic age to the ¯ora based primarily upon what he considered its close similarity to the ¯oras from Yorkshire. Stipanicic and Bonetti C1970) considered the age of the Hope Bay ¯ora in their comprehensive review of Argentine Jurassic ¯oras. They believed it showed an equal degree of af®nity with the Rajmahal ¯oras of India Cwhich they regarded as Lower Cretaceous) and the Middle Jurassic and Neocomian CLower Cretaceous) ¯oras of Europe. They therefore concluded that the Hope Bay ¯ora was probably of latest Jurassic age, although they did not discount that it could be earliest Cretaceous. This was accepted by many palaeobotanists studying Argentine ¯oras Ce.g. Herbst 1971; Baldoni 1981a, b; Baldoni and Olivero 1983) and geologists interpreting the stratigraphy, palaeogeography and volcanic arc history of the Antarctic Peninsula Ce.g. Thomson et al. 1983; Farquharson 1983a, 1984; Farquharson et al. 1984; del Valle and Fourcade 1986; Macdonald et al. 1988). However, there are two main problems with Stipanicic and Bonetti's age argument. Firstly, there is considerable uncertainty as to the age of the Rajmahal ¯oras. Rao C1953) interpreted them as probably Middle Jurassic or possibly Early Jurassic, but this was based largely on the presence of species with extensive age ranges CRees 1990). Rao's view was accepted by Shah et al. C1973), who considered that plant biostratigraphy was the only reliable means of dating the ¯oras. In contrast, McDougall and McElhinny C1970) argued that they were Albian C100±105 Ma) based on K-Ar dating. According to Sengupta C1988), however, these dates were based on poorly localised basalt samples that cannot de®nitely be associated with the ¯oras. At present, their age can only be estimated as somewhere between ?Early Jurassic and ?Albian, and thus provides little guide to the age of the Hope Bay ¯ora. Secondly, it is dif®cult to accept the accuracy of stratigraphical correlations between Mesozoic ¯oras from such widely differing regions as Antarctica and Europe. It is far better to compare them with more `local' ¯oras from similar palaeolatitudes Ce.g. Argentina; Bonetti 1963, 1974) but, curiously, Stipanicic and Bonetti C1970) did not do this. However, they did accept the taxonomic determinations of earlier Argentine palaeobotanists Ce.g. MeneÂndez 1956) who had assigned a Middle Jurassic age to the ¯ora from Bajo de los Baguales, NeuqueÂn Province, based on its close af®nity with the Hope Bay ¯ora. They even assigned a Middle±Late Bajocian CMiddle Jurassic) age to the Bajo de los Baguales ¯ora, based largely upon the probable Bajocian age assigned to it by Volkheimer C1968, 1969) from palynological correlations. However, they did not assign this age to the closely similar ¯ora from Hope Bay, preferring instead to compare it with those from India and Europe. Palaeobotanists who have subsequently studied Jurassic Argentine ¯oras Ce.g. from CanÄadoÂn del Zaino and CanÄadoÂn Asfalto; Baldoni 1981a) have recognised their close af®nity with Hope Bay and dated them as latest Jurassic±earliest Cretaceous based on Stipanicic and Bonetti's age assignment for the Hope Bay ¯ora. However, this ignores the fact that Stipanicic and Bonetti C1970) had assigned Middle Jurassic ages to these Argentine ¯oras. A certain degree of circularity is evident. The Hope Bay ¯ora was dated by

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 76 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Stipanicic and Bonetti on the basis of correlations with Northern Hemisphere and poorly-dated Indian ¯oras. This was then used to revise the ages of similar Argentine ¯oras Ce.g. from CanÄadoÂn del Zaino, CanÄadoÂn Asfalto and Lago Argentino; Baldoni 1981a, b). However, these should have been considered by Stipanicic and Bonetti when assigning the initial age Csee Rees 1990 for more detailed discussion). Herbst C1971) revised the species of Cladophlebis from Argentina and Antarctica. He mentioned in a footnote Cp. 268) that the Hope Bay ¯ora had various elements in common, or close similarities, with Triassic, Liassic and Middle Jurassic ¯oras from Argentina. Indeed, he remarked that `this last fact could slightly alter the previous argument' Ci.e. that of Stipanicic and Bonetti 1970, for a latest Jurassic or earliest Cretaceous age for the Hope Bay ¯ora). However, he did not expand upon his comments and assigned a Late Jurassic age to the Hope Bay ¯ora in the main text of his paper, effectively utilising the age determination Cbased on extra-Argentine correlations) of Stipanicic and Bonetti C1970). Archangelsky and Baldoni C1972) and Baldoni C1979, 1986) believed that the Hope Bay ¯ora is latest Jurassic to earliest Cretaceous in age, based on the reported presence there of Ptilophyllum antarcticum Archangelsky and Baldoni non Halle. Specimens of P. antarcticum Cwith cuticle preserved) occur in Argentine ¯oras of latest Jurassic±Early Cretaceous age Cfrom the Spring Hill and Baquero formations). As we have argued in the systematic discussion of Z ? antarcticus, however, the Hope Bay and Argentine specimens are not conspeci®c and are thus irrelevant to their relative dating Csee also Gee 1989; Rees 1990, 1993c). In addition to the Argentine records, Ptilophyllum antarcticum may also occur in the northern Antarctic Peninsula CBaldoni 1986), in upper Oxfordian±Berriasian marine deposits of the NordenskjoÈld Formation CFarquharson 1982, 1983b). However, these sparse, fragmentary and poorly preserved impression fossils now provide the only reason for applying the speci®c epithet antarcticum to this species of Ptilophyllum. In summary, age assignments for the Hope Bay ¯ora prior to Rees C1990, 1993a, c) were based upon correlations with Northern Hemisphere ¯oras and/or imprecisely dated Indian ¯oras, or else used poorly- de®ned species. They have tended to ignore the poor preservation of the Antarctic fossils, which limits the reliability of their identi®cations. In this study, new palaeobotanical information is combined with the use of morphologically consistent genera and species which have restricted age ranges, largely independently dated, in order to provide a new and more complete assessment of its composition and age.

Revised palaeobotanical age assignment To obtain a more reliable age for the Hope Bay and Botany Bay ¯oras, the ranges of certain stratigraphically signi®cant taxa have been examined. In each case, the reliability of their previous determinations and age assignments is assessed, the latter being based, wherever possible, on independent controls Ce.g. palynology, fossiliferous marine intercalations, radiometric dating). This approach, com- bined with an understanding of geological ®eld relations and stratigraphical limitations of the data should ensure more rigorous biostratigraphical correlations. Attention is focused on correlations with Argentina because of its close geographical proximity and ¯oral af®nity throughout the Mesozoic, and the fact that it often has independently dated ¯oras. They therefore provide more valid comparisons than those with poorly-dated Indian ¯oras Ce.g. Bose et al. 1990), or poorly-known Jurassic ¯oras from Australia, New Zealand and South Africa Ce.g. White 1981; Oliver et al. 1982; Anderson and Anderson 1985). Where independent age controls are lacking and when ¯oras are poorly preserved, only those plant genera and species with reliable and consistent macroscopic features should be used for biostratigraphical purposes. Ideally, such correlations should also be made only with taxa that have a restricted stratigraphical range, but these are rare in most Jurassic and Early Cretaceous ¯oras. However, one such genus, Goeppertella, is present at Hope Bay CRees 1993a) and Botany Bay CRees 1993a; Morel et al. 1994), and this is supplemented by evidence from four other taxa. Goeppertella. Prior to Rees C1993a) and Morel et al. C1994), the only records of Goeppertella in the Southern Hemisphere were from Upper Triassic or Lower Jurassic beds in Argentina CHerbst 1964a, 1966, 1968, 1975, 1993; Arrondo and Petriella 1980, 1982; Petriella and Arrondo 1984; Baldoni 1987). Although less reliable for correlative purposes, it is worth noting that most species of Goeppertella from the Northern Hemisphere are from the Upper Triassic, with some possibly ranging into the Lower Jurassic

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 77 but none being known from younger ¯oras CMoÈller and Halle 1913; OÃ ishi and Yamasita 1936; Harris 1946; Iwai et al. 1975; Sichuan Stratigraphic Group 1976; Yunnan Stratigraphic Group 1976; Zhejiang Stratigraphic Group 1979; Dobruskina 1982; Wu 1982; Fujian Bureau of Geology and Mineral Resources 1985; Rao et al. 1987; Guangdong Bureau of Geology and Mineral Resources 1988; Hubei Bureau of Geology and Mineral Resources 1990). Arrondo and Petriella C1982) concluded that Goeppertella is a good index fossil `essentially for Liassic [Lower Jurassic] times' and that the occurrence of subsidiary elements Ci.e. rachial pinnules; Rees 1993a) is `a very signi®cant taxonomic character'. However, two of the Argentine species, G. frenguelliana and G. herbstii, from Cordon de Esquel and Estancia La Juanita, are not independently dated as Early Jurassic CHerbst 1968; Stipanicic and Bonetti 1970; Petriella and Arrondo 1984) and so it cannot be entirely discounted that the genus may extend into the Middle Jurassic. Nevertheless, the presence of Goeppertella at Hope Bay and Botany Bay, together with the other taxa, favours an Early Jurassic age. Certainly, a Late Jurassic or Early Cretaceous age Ce.g. Stipanicic and Bonetti 1970) can be discounted.

Dictyophyllum. Although we do not recognise Dictyophyllum in the Hope Bay and Botany Bay ¯oras, the fact that fragmentary specimens of Dictyophyllum and Goeppertella may sometimes be indistinguishable means that we should consider the stratigraphical range of Dictyophyllum. The genus is common globally in ¯oras of Triassic±late Middle Jurassic age Ce.g. Stipanicic and Bonetti 1970; Herbst 1975; Dobruskina 1982; Vakhrameev 1991). In Argentina, it occurs in independently dated Early Jurassic CHerbst 1975) and Crarely) Middle Jurassic CStipanicic and Bonetti 1970) ¯oras. One specimen from the poorly preserved Arroyo CaÂnogas ¯ora of Chubut was recorded as Dictyophyllum sp., but was neither described nor illustrated CBaldoni and Olivero 1983). The ¯ora was assigned a latest Jurassic±earliest Cretaceous age by those authors, but there is nothing in the ¯ora to support this and its relationship with the nearby fossiliferous marine beds Cwhich were used to date it) is obscured by exposure gaps and faulting CBaldoni and Olivero 1983, ®g. 1). Herbst C1975) stated that, elsewhere in Gondwana, Dictyophyllum Cincluding its later synonym Thaumatopteris; Herbst 1975) has been found in Triassic beds of South Africa Cone species) and Australia Cthree species) as well as in the Lower Jurassic of New Zealand Cone species). Although Appert C1973) had assigned a single fragmentary specimen from Madagascar to Dictyophyllum sp., belonging to what he considered to be a Late Jurassic ¯ora, this determination is not certain CAppert, pers. comm. 1996). In the Northern Hemisphere, Dictyophyllum is most commonly represented in Middle Jurassic or older ¯oras, with only a few rare and `relictual' younger occurrences Ce.g. Vakhrameev 1991). These include some forms that have been incorrectly identi®ed as Dictyophyllum or else come from ¯oras that may have been dated incorrectly. For example, Dictyophyllum roemari from the English Wealden CLower Cretac- eous) CSeward 1894) was assigned instead to Hausmannia dichotoma by Watson C1969). Hausmannia is also a dipteridaceous fern but, unlike Goeppertella and Dictyophyllum, has an extensive record, occurring in at least Late Triassic through Late Cretaceous ¯oras Ce.g. Dobruskina 1982; Vakhrameev 1991). In summary, reliable records of Dictyophyllum combined with their stratigraphical abundances at least favour a pre-Cretaceous, even pre-Late Jurassic, age for ¯oras containing this genus.

Sagenopteris nilssoniana. This is present at Hope Bay and Botany Bay CRees 1993b), and is otherwise known only from Upper Triassic and Lower Jurassic ¯oras CHarris 1932; Frenguelli 1941; Rees 1993b; Barbacka and BoÂka 2000).

Archangelskya furcata. Other than Hope Bay and Botany Bay CRees and Cleal 1993), the only known occurrence of this form-genus is in the Liassic CLower Jurassic) of RõÂo Atuel, Argentina CHerbst 1964b). However, the fronds are highly polymorphic CRees and Cleal 1993) and there may be younger specimens from elsewhere, currently assigned to other genera.

Dicroidium feistmantelii. Townrow C1958, p. 29) stated that the genus normally does not extend above the lower Upper Triassic, although there are some possible occurrences from higher horizons. Botany Bay is currently the youngest-known occurrence of the genus.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 78 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Pachypteris indica. The Indian records of this species are poorly dated. However, the Antarctic specimens Cfrom Hope Bay and Botany Bay) are very similar, both macro- and microscopically, to those from Bajo de los Baguales, Argentina, described Cas Sphenopteris bagualensis) by MeneÂndez C1956). That ¯ora has been dated palynologically as Bajocian or possibly Bathonian Ci.e. Middle Jurassic; Volkheimer 1968, 1969). This at least contributes to favouring a Jurassic rather than Cretaceous age for the Hope Bay and Botany Bay ¯oras. The close similarity of the Hope Bay and Botany Bay ¯oras C80 per cent of the Botany Bay species also occur at Hope Bay, including G. woodii, S. nilssoniana, A. furcata and P. indica), the similarity of their depositional environments CFarquharson 1984) which minimises the effects of taphonomic bias, and their close geographical proximity, all indicate that they are contemporaneous. The palaeobotanical evidence strongly suggests an Early Jurassic age; it certainly precludes a Late Jurassic or Cretaceous age for either ¯ora.

Radiometric evidence As with Hope Bay, the plant-bearing sedimentary sequence at Botany Bay underlies volcanic rocks of the Antarctic Peninsula Volcanic Group. Their exact stratigraphical relationship is obscured by faulting, but there is little doubt that the plant beds underlie the volcanics and are apparently separated from them by an unconformity CFarquharson 1984; Rees 1993c). Sm-Nd dating of primary igneous garnets from an andesitic sill within the volcanic rocks has yielded an age of 152 6 8 Ma CMillar et al. 1990). Based on the current IUGS International Stratigraphic Chart CRemane et al. 2002) this indicates that the sill is early Callovian±middle Kimmeridgian in age allowing for the 68 Ma dating uncertainty. The age of the volcanic rocks into which the sill is intruded is unknown, but obviously must predate the late Middle or Late Jurassic. It clearly rules out a Cretaceous age for the Botany Bay Cand closely similar Hope Bay) plant beds, and is fully compatible with the palaeobotanical evidence that they are most probably Early Jurassic. The radiometric evidence at Botany Bay has been placed in the broader context of Jurassic magmatism in western Gondwana by Riley and Leat C1999). Based on various lines of evidence, including the arguments set out in Rees C1993c), they assigned an Early Jurassic±early Middle Jurassic age to the Botany Bay Group, which includes the plant-bearing sequences at Hope Bay and Botany Bay CFarquharson 1984). Other geological evidence from the region that apparently supported a latest Jurassic or Early Cretaceous age for these ¯oras Ce.g. Stipanicic and Bonetti 1970) includes: the presence of lithologically similar sequences dated as Early Cretaceous CThomson 1981; Farquharson 1984); Early Cretaceous Rb-Sr radiometric ages from two localities in the region CPankhurst 1982); and the supposedly older relationship of Upper Jurassic marine sequences of the nearby NordenskjoÈld Formation CFarquharson 1982) to localities Cincluding Hope Bay and Botany Bay) assigned to the Botany Bay Group CFarquharson 1984). However, none of this evidence can withstand critical appraisal Csee Rees 1993c for detailed discussion). This, together with the new palaeobotanical information, led Rees C1993c) to conclude that terrestrial sediments were deposited in at least parts of the northern Antarctic Peninsula during the early Jurassic. He also proposed a revision of the model suggested by Farquharson C1983a) for the late Mesozoic history of the northern Antarctic Peninsula region. Instead of commencing in the Early Cretaceous as suggested by Farquharson C1983a, 1984), it is more probable that magmatic arc uplift occurred and an integral landmass existed in this area from Early Jurassic times onwards CRees 1993c).

P A L A E O E N V I R O N M E N T A N D P A L A E O C L I M A T E The Hope Bay and Botany Bay ¯oras comprise stems of sphenophytes CEquisetum) as well as fern and gymnosperm foliage CSagenopteris, pteridosperms, cycadophytes and conifers). No ginkgophytes or macrophyllous conifers have been found, despite the intensive collecting of many specimens from these localities, with the sole possible exception of the `leaf of unknown af®nity' from Hope Bay. The lithologies in which these plants are preserved represent ¯oodplain deposits, with the silts and ®ne sands settling out, along with the plant remains, from slow-moving bodies of water CText-®g. 6). Their deposition was often punctuated by ®ning-upward sequences of coarse and medium grained sands which

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 79

TEXT-FIG. 6. Generalised section measured at Botany Bay, modi®ed from Farquarson C1984) and Rees C1993c).

represent crevasse splay deposits, along with mudstones representing lacustrine deposits CFarquharson 1984). According to Farquharson, the overall ¯oodplain environment comprised low-sinuosity rivers and shallow lakes. The presence of abundant plant remains within the siltstone facies indicates that the ¯oodplain across which the rivers ¯owed was well-vegetated and had a high water table. Differences in ¯oodplain vegetation preserved in the sedimentary sequence may be due to: variations in ¯ow strength and direction during ¯ood episodes, changes in vegetational source areas, variable mixing of in situ and transported plants, relative distance of depositional sites from the original plant growth sites, and the size of plant fragments transported Csee Rees 1993d). Another factor to be considered is genuine regional climate change resulting in oscillations between wet and dry conditions, re¯ected in the vegetation. Text-®gure 7 shows changes in plant associations at the different horizons sampled systematically Cby PMR) at Botany Bay. Rather than reproduce the entire 115 m measured section in detail, only the main

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 80 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 81 plant-bearing horizons are shown; intervening mudstone, coarse sandstone and conglomerate lithologies, which were either barren or contained only unidenti®able stems and other fragments, have been excluded. There is no discernible difference in lithology between the horizons shown, most of them being siltstones, with rare very ®ne or ®ne-grained sandstones. Consequently, the ®gure is not to scale; several horizons may be within a metre of each other and there may be several metres between individual horizons elsewhere Csee Rees 1990, 1993d for more detailed sectional information). Additionally, the number of specimens collected from each horizon varies and so some caution is needed when interpreting the results shown in Text-®gure 7. This is due, at least in part, to the constraints of Antarctic ®eldwork; weather conditions and logistical problems meant that only three weeks of a three month ®eld season were spent collecting new material and logging sections at Botany Bay. The need to collect as representative a sample as possible from all levels at this new locality meant that sampling was inconsistent through the sequence. Also, the amount of material that could be collected was dependent on space available on the sledges. The aim here is to show general patterns of plant associations at Botany Bay and their environmental inferences, despite the above caveats which indicate that further ®eldwork is necessary. Relative abundances of ®eld-identi®ed specimens were recorded for each horizon, based on ®eld frequency estimates CRees 1990). These were re®ned, where possible, to species-level estimates based on laboratory identi®cations. Species were then grouped into ®ve categories, based broadly on a combination of their taxonomic and morphological characters: C1) microphyllous cycadophytes and microphyllous conifers, as well as Pachypteris indica Cwith its apparently coriaceous lamina and sunken stomata), C2) `ferns', including Archangelskya furcata, C3) macrophyllous cycadophytes, C4) Caytoniales, and C5) Equisetales. The available evidence shows that the `microphylls' Ccategory 1, possibly adapted to drier conditions, with foliar adaptations for minimising water loss), and those such as the macrophyllous cycadophytes and Equisetum Ccategories 3 and 5, which probably grew in wetter environments) tend to be mutually exclusive. This could be interpreted as re¯ecting ¯uctuations in the regional climate between dry and ever- wet conditions. Alternatively, the assemblages apparently adapted to drier conditions may represent the vegetation of well-drained areas distal to the ever-wet depositional sites, with periodically higher rainfall or storms resulting in their transport to the depositional sites. Indeed, there is no lithological evidence for periodically dry climatic conditions in the region. The presence of braided stream, debris ¯ow and sheet- ¯ood sedimentary deposits at both Botany Bay and Hope Bay suggests at least seasonally high rainfall with periodic ¯ooding CFarquharson 1984). Based solely upon sedimentological evidence, Birkenmajer C1993, p. 36) also envisaged a `vertically diversi®ed climate, possibly including both humid Clowland) and arid Chighland) habitats' at Hope Bay. The near-continuous presence of ferns Cwhich usually need moist conditions for growth and reproduction, as well as being relatively fragile and thus unlikely to survive signi®cant transportation) also indicates that the depositional sites were everwet. Furthermore, the variation in horizon abundance of Equisetum from 0±100 per cent CText-®g. 7) indicates absence, variable mixing with other taxa, or in situ dominance, again most probably as a result of variations in ¯ow patterns. We therefore envisage environments at Botany Bay Cand by inference Hope Bay) in which Equisetum, ferns, Sagenopteris and macrophyllous cycadophytes were growing fairly near to where they were buried.

TEXT-FIG. 7. Plant associations and percentage abundances based on ®eld and laboratory estimates at different sampling horizons within the sequence at Botany Bay. Taxa are broadly arranged according to morphology rather than taxonomy, so that microphyllous forms are on the left and larger-leaved forms Cas well as Equisetum) are to the right. C1) `microphylls': Zamites? antarcticus, Otozamites? latior, O.? linearis, Brachyphyllum sp., Pagiophyllum cf. crassifolium, P. feistmantelii, P. sp., Elatocladus confertus, Pachypteris indica. C2) `ferns': Cladophlebis antarctica, C. denticulata, C. oblonga, Todites williamsonii, Cf. Matonidium sp., Coniopteris lobata, C. sp. A, Goeppertella woodii, Hausmannia papilio, Archangelskya furcata. C3) `macrophylls': Ctenis sp. cf. exilis, Taeniopteris taeniopteroides, Pseudoctenis? ensiformis. C4) Caytoniales: Sagenopteris nilssoniana, Caytonanthus sp. C5) Equisetales: Equisetum laterale.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 82 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2 Major ¯ood events would have occasionally carried distal microphyllous forms down to these sites. Although further ®eldwork is needed to con®rm this model, we believe that the changing plant associations re¯ect complex variations in ¯oodplain deposition rather than regional climate change. The absence of ginkgophytes and unequivocal macrophyllous conifers from these ¯oras, despite intensive collecting, probably re¯ects the prevailing climate of the time. Such plants had deciduous abscissing leaves, which were probably an adaptation to seasonally cool temperate and/or dark conditions Csee Rees et al. 2000 for further discussion). Although patterns of plant associations at Botany Bay are complex, we can interpret the prevailing climatic conditions under which these diverse ¯oras grew Cat both Botany Bay and Hope Bay) to be warm temperate Cwe de®ne warm and cool temperate using the Walter 1985 scheme as modi®ed by Ziegler 1990 and Rees et al. 2000, 2002). Studies of fossil tree rings CFrancis 1986) provide some support for the foliar evidence that most plants at Hope Bay and Botany Bay grew under warm temperate conditions, with no evidence of aridity. Differences in precipitation probably played a greater role than temperature on vegetational growth and preservation. Such detailed palaeobo- tanical studies can be incorporated in global syntheses; patterns of Jurassic phytogeography and climates, based on quantitative analyses of global palaeobotanical data, lithological distributions and palaeoclimate model results, are described by Rees et al. C2000).

C O N C L U S I O N S Previous arguments advocating a post-Early Jurassic age for the Hope Bay ¯ora are largely invalid and the new palaeobotanical information indicates that it should certainly no longer be considered as Late Jurassic or Cretaceous. The presence of Goeppertella in the Hope Bay and Botany Bay ¯oras indicates that they are most probably Early Jurassic, based upon the previously recorded age range of this genus. The occurrence of Sagenopteris nilssoniana, Archangelskya furcata, Dicroidium feistmantelii and Pachypteris indica provides some additional support for this age, and the large number of species common to both ¯oras indicates that they should be regarded as contemporaneous. Although there are some similarities to Middle or even Late Jurassic ¯oras elsewhere and, intriguingly, certain key taxa CGoeppertella, Sagenopteris nilssoniana and Dicroidium feistmantelii) also occur in Late Triassic ¯oras, an Early Jurassic age is favoured on presently available evidence. Care must be taken when assigning ages to ¯oras in the absence of independent stratigraphical controls. Only those taxa with reliable and consistent taxonomic characters as well as a restricted stratigraphical range can be used to assign ages with any reasonable degree of certainty. It is relatively easy to identify taxa common to different ¯oras, but harder to know their stratigraphical ranges and to understand their relevance other than in the broadest sense of `¯oristic similarity'. Radiometric evidence from Botany Bay CMillar et al. 1990), as well as local ®eld relations, supports an Early Jurassic age for the Hope Bay and Botany Bay ¯oras. The revised age provides the ®rst direct evidence that terrestrial sediments were deposited in at least parts of the northern Antarctic Peninsula during the Early Jurassic. It is noteworthy that no marine beds unequivocally Jurassic or younger are known from the central area of the northern Antarctic Peninsula CRees 1993c). This supports the idea that an integral landmass existed in this area from Early Jurassic times onwards CRees 1993c), rather than from the Early Cretaceous as suggested previously Ce.g. Farquharson 1984). The palaeobotanical and geochronological results also indicate that, in the northern Antarctic Peninsula region, magmatic arc uplift commenced in the Early Jurassic and that volcanic activity continued from this time onwards CRees 1993c). This is the currently accepted interpretation Ce.g. Riley and Leat 1999). Our results provide new information that can be used to re®ne palaeogeographical reconstructions, particularly regarding the relative positions of the Antarctic Peninsula, the Falklands Plateau and southern South America in the Mesozoic. The present taxonomic and age revision of these diverse Antarctic ¯oras should also provide the impetus for a reappraisal of similar ¯oras from elsewhere in Gondwana. Many of these, particularly from Argentina, were dated on the basis of comparison with the Hope Bay ¯ora. The careful use of stratigraphically signi®cant taxa combined with more local `intra-Gondwanan' comparisons should lead to more accurate dating of these other ¯oras, ultimately contributing towards a more complete understanding of Mesozoic phytogeography and climates.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 83 We end by quoting Seward's C1931, p. 371) comments on the Hope Bay ¯ora. `As Halle points out . . . the plants show no sign of stunted growth or any of the features which we now associate with vegetation of polar regions. If the present position of Graham Land in relation to the South Pole is the same as it was in the middle of the Jurassic period the problem of climate is raised in an acute form. On the borders of Antarctica, in a glaciated country practically barren of vegetation, we ®nd a comparatively rich ¯ora strikingly similar in its general composition . . . to the ¯ora furnished by the Jurassic rocks of Yorkshire. This astonishing fact may well incline us favourably to consider the possibility of drifting continents and to hazard the opinion that Graham Land was not always where it is today.' Seward was of course correct in supporting Wegener's C1915) ideas of continental drift, for which palaeobotany provides much support. However, in this particular case, Seward was wrong; currently accepted Early Jurassic palaeogeographies place Graham Land at similar latitudes as to today. Its apparently anomalous vegetation was instead due to the global climate of that time being markedly different from today's, with a much lower temperature gradient between the tropics and the ice-free poles CRees et al. 2000).

Acknowledgements. We thank the following for their helpful comments and advice on various aspects of the work dealt with here: W. G. Chaloner, M. R. A. Thomson, J. Kvacek, C. H. Shute, R. A. Spicer and C. R. Hill. We also thank J. van Konijnenburg-van Cittert for her detailed and constructive review. The Natural Environment Research Council funded earlier stages of this work Cfor PMR), who is also grateful to the British Antarctic Survey, particularly P. CPink) Wood of Sledge Sierra, for logistical support in the ®eld. The use of facilities at The Natural History Museum CLondon), and the Universities of London, SaÄo Paulo, Rio de Janeiro, Oxford, and Chicago, is also gratefully acknowledged. The illustrations in this volume are largely based on photographs by P. Crabb CNHM, London) to whom we are deeply indebted.

R E F E R E N C E S

ANDERSON, J. M. and ANDERSON, H. M. 1983. Palaeo¯ora of southern Africa, Molteno Formation VTriassic). Vol. 1. A. A. Balkema, Rotterdam, v ‡ 227 pp. ÐÐ ÐÐ 1985. Palaeo¯ora of southern Africa. Prodromus of South African mega¯oras Devonian to Lower Cretaceous. A. A. Balkema, Rotterdam, 423 pp. ANTEVS, E. 1914. Die Gattung Thinnfeldia Ett. und Dicroidium Goth. Kungliga Svenska Vetenskapsakademie Handlingar, 51 C6), 1±71, 5 pls. APPERT, O. 1973. Die Pteridophyten aus dem Oberen Jura des Manamana in SuÈdwest-Madagaskar. Schweizerische PalaÈontologische Abhandlungen, 94, 1±62. ARCHANGELSKY, S. 1968. Studies on Triassic fossil plants from Argentina. IV. The leaf genus Dicroidium and its possible relation to Rhexoxylon stems. Palaeontology, 11, 500±512, pls 97±98. ÐÐ and BALDONI, A. M. 1972. RevisioÂn de las Bennettitales de la FormacioÂn Baquero CCretaÂcico Inferior), Provincia de Santa Cruz. I. Hojas. Revista del Museo de La Plata, SeccioÂn Paleontologia, 44, 195±265. ARRONDO, O. G. and PETRIELLA, B. 1980. AlicuraÂ, nueva localidad plantõÂfera liaÂsica de la provincia de NeuqueÂn, Argentina. Ameghiniana, 17, 200±215. ÐÐ 1982. RevisioÂn del geÂnero Goeppertella Oà ishi et Yamasita emend. CGoeppertelloideae-Dipteridaceae). Ameghiniana, 19, 67±78. BALDONI, A. M. 1977. Nota sobre Sueria rectinervis MeneÂndez del Cretacico Inferior de la FormacioÂn BaqueroÂ, provincia de Santa Cruz. Ameghiniana, 14, 301±304. ÐÐ 1979. Nuevos elementos paleo¯orõÂsticos de la tafo¯ora de la FormacioÂn Spring Hill, limite JuraÂsico-CretaÂcico, subsuelo de Argentina y Chile austral. Ameghiniana, 16, 103±119. ÐÐ 1981a. Tafo¯oras juraÂsicas y eocretaÂcicas de AmeÂrica del Sur. 359±391. In VOLKHEIMER, W. and MUSACCHIO, E. A. Ceds). Cuencas sedimentarias del JuraÂsico y CretaÂcico de AmeÂrica del Sur, 2. Comite Sudamericano del JuraÂsico y CretaÂcico, Buenos Aires, 713 pp. ÐÐ 1981b. Tafo¯ora del Jurasico Superior de la zona de Lago Argentino, provincia de Santa Cruz. Ameghiniana, 18, 97±102. ÐÐ 1986. CaracterõÂsticas generales de la mega¯ora, especialmente de la especie Ptilophyllum antarcticum, en el JuraÂsico Superior ± CretaÂcico Inferior de AntaÂrtida y Patagonia, Argentina. Boletim IG-USP, Instituto de GeocieÂncias, Universidade de SaÄo Paulo, 17, 77±87. ÐÐ 1987. Mega¯oras del JuraÂsico inferior de la Patagonia extraandina, con algunas consideraciones sobre Venezuela y Colombia. Comite Sudamericano del JuraÂsico y CretaÂcico: bioestratigrafõÂa de los sistemas regionales del JuraÂsico y CretaÂcico de AmeÂrica del Sur, 1, 159±199.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 84 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2

ÐÐ and OLIVERO, E. 1983. Plantas fosiles de la FormacioÂn Lago la Plata procedentes de Arroyo CaÂnogas, Provincia de Chubut, Argentina. Ameghiniana, 20, 34±40. ÐÐ and RAMOS, V. A. 1981. Nuevas localidades con plantas foÂsiles cretaÂcica en la Cordillera PatagoÂnica Cprovincia de Santa Cruz, RepuÂblica Argentina). Actas, VIII Congress Geologica Argentina, 4, 743±759. ÐÐ and TAYLOR, T. N. 1983. Plant remains from a new Cretaceous site in Santa Cruz, Argentina. Review of Palaeobotany and Palynology, 39, 301±311. BARALE, G., PHILIPPE, M., TORRES, T. and COVACEVICH, V. 1994. Triassic ¯oras from Williams Point, Livingston Island CSouth Shetland, northern Antarctica). Comptes Rendus de l'AcadeÂmie des Sciences, SeÂrie II, 319, 141±147. BARBACKA, M. 1994. Komlopteris Barbacka, gen. nov., a segregate from Pachypteris Brongniart. Review of Palaeobotany and Palynology, 83, 339±349. ÐÐ and BO KA, K. 2000. The stomatal ontogeny and structure of the Liassic pteridosperm Sagenopteris CCaytoniales) from Hungary. International Journal of Plant Sciences, 161, 149±157. BERCHTOLD, F. and PRESL, J. S. 1820. O pùirozenosti Rostlin. K. W. Endersa, Prague, 322 pp. BIRKENMAJER, K. 1993. Jurassic terrestrial clastics CMount Flora Formation) at Hope Bay, Trinity Peninsula CWest Antarctica). Bulletin of the Polish Academy of Science, 41, 23±38. BLASCHKE, P. M. and GRANT-MACKIE, J. A. 1976. Mesozoic leaf genus Taeniopteris at Port Waikato and Clent Hills, New Zealand. New Zealand Journal of Geology and Geophysics, 19, 933±941. BOERSMA, M. 1972. The heterogeneity of the form-genus Mariopteris Zeiller. A comparative morphological study with special reference to the frond composition of west-European species. Elinkwijk, Utrecht, 172 pp. BONETTI, M. I. R. 1963. Florula mesojuraÂsica de la Zona de TaquetreÂn CCanÄadoÂn del Zaino), Chubut. Revista del Museo Argentino de Ciencias Naturales `Bernardino Rivadavia', Paleontologia, 1 C2), 23±43. ÐÐ 1974. Florula Jurasica del Lago Argentino CSanta Cruz). Resumenes I Congreso Argentino de Paleontologia y Bioestratigra®a, TucumaÂn, Argentina, 9±10. BOSE, M. N. and BANERJI, J. 1981. Cycadophytic leaves from Jurassic±Lower Cretaceous rocks of India. Palaeobotanist, 28±29, 218±300. ÐÐ ÐÐ 1984. The fossil ¯oras of Kachchh. I. Mesozoic megafossils. Palaeobotanist, 33, 1±189. ÐÐ and MAHESHWARI, H. K. 1973. Some detached seed-scales belonging to the Araucariaceae from the Mesozoic rocks of India. Geophytology, 3, 205±214. ÐÐ PAL, P. K. and HARRIS, T. M. 1985. The Pentoxylon plant. Philosophical Transactions of the Royal Society of London, Series B, 310, 77±108. ÐÐ and ROY, S. K. 1968. On the occurrence of Pachypteris in the Jabalpur Series of India. Palaeobotanist, 16, 1±9. ÐÐ and SAH, S. C. D. 1968. Some pteridophytic remains from the Rajmahal Hills, Bihar. Palaeobotanist, 16, 12±28. ÐÐ TAYLOR, E. L. and TAYLOR, T. N. 1990. Gondwana ¯oras of India and Antarctica ± a survey and appraisal. 118±148. In TAYLOR, T. N. and TAYLOR, E. L. Ceds). Antarctic paleobiology: its role in the reconstruction of Gondwana. Springer-Verlag, New York, 261 pp. BOWER, F. O. 1908. The origin of a land ¯ora. Macmillan, London, xi ‡ 727 pp. BRONGNIART, A. 1825. Observations sur les veÂgeÂtaux fossiles renfermeÂs dans les GreÁs de Hoer en Scanie. Annales des Sciences Naturelles, 4, 200±219, pls 11±12. ÐÐ 1828. Prodrome, d'une Histoire des veÂgeÂtaux fossiles. Dictionnaire des Sciences Naturelles, 57, 1±223. ÐÐ 1829. Histoire des veÂgeÂtaux fossiles. Volume 1 C3). G. Dufour and E. D'Ocagne, Paris, pp. 137±168, pls 28, 30±36, 38±41, 44±45. ÐÐ 1831. Histoire des veÂgeÂtaux fossiles. Volume 1 C5±6). G. Dufour and E. D'Ocagne, Paris, pp. 209±264, pls 50, 53, 57±61, 61bis, 62±65, 67±82. ÐÐ 1834. Histoire des veÂgeÂtaux fossiles. Volume 1 C8±9). G. Dufour and E. D'Ocagne, Paris, pp. 289±336, pls 82A, 98±114, 117±118, 124, 127±128, 130. ÐÐ 1849. Tableau des genres de veÂgeÂtaux fossiles considereÂs sous le point de vue de leur classi®cation botanique et de leur distribution geÂologique. L. Martinet, Paris, 127 pp. CANTRILL, D. 1995. The occurrence of the fern Hausmannia Dunker CDipteridaceae) in the Cretaceous of Alexander Island, Antarctica. Alcheringa, 19, 243±254. CHAPMAN, J. L. and SMELLIE. J. L. 1982. Cretaceous fossil wood and palynomorphs from Williams Point, Livingston Island, Antarctic Peninsula. Review of Palaeobotany and Palynology, 74, 163±192. CLEAL, C. J. and REES, P. M. 2003. The Middle Jurassic ¯ora from Stones®eld, Oxfordshire, UK. Palaeontology, 46, 739±801. ÐÐ and THOMAS, B. A. 1999. Plant fossils. A history of land vegetation. Boydell Press, Woodbridge, 188 pp., 128 pls. DOBRUSKINA, I. A. 1982. Triassic ¯ora of Eurasia. Trudy Akademii Nauk SSSR, Seria Geologicheskaya, 365, 1±195. [In Russian].

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 85

DOUGLAS, J. G. 1969. The Mesozoic ¯oras of Victoria, parts 1 and 2. Memoirs of the Geological Survey of Victoria, 28, 1±310. DRINNAN, A. N. and CHAMBERS, T. C. 1985. A reassessment of Taeniopteris daintreei from the Victorian Early Cretaceous: a member of the Pentoxylales and a signi®cant Gondwanaland plant. Australian Journal of Botany, 33, 89±100. ÐÐ ÐÐ 1986. Flora of the Lower Cretaceous Koonwarra Fossil Bed CKorumburra Group), South Gipps- land, Victoria. 1±77. In JELL, P. A. and ROBERTS, J. Ceds). Plants and invertebrates from the Lower Cretaceous Koonwarra Fossil Bed, South Gippsland, Victoria. Memoirs of the Association of Australasian Palaeontologists, 3, 205 pp. ETTINGSHAUSEN, C. 1852. Begrundung einiger neuen oder nicht genau bekannten Arten der Lias und Oolith Flora. Abhandlungen der Kaiserlich-KoÈniglichen Geologischen Reichsanstalt Wein, 1 C3), 1±10. FARQUHARSON, G. W. 1982. Late Mesozoic sedimentation in the northern Antarctic Peninsula and its relationship to the southern Andes. Journal of the Geological Society of London, 139, 721±727. ÐÐ 1983a. Evolution of late Mesozoic sedimentary basins in the northern Antarctic Peninsula. 323±327. In OLIVER, R. L., JAMES, P. R. and JAGO, J. B. Ceds). Antarctic earth science. Australian Academy of Science and Cambridge University Press, Canberra and Cambridge, 697 pp. ÐÐ 1983b. The NordenskjoÈld Formation of the northern Antarctic Peninsula: an Upper Jurassic radiolarian mudstone and tuff sequence. British Antarctic Survey, Bulletin, 60, 1±22. ÐÐ 1984. Late Mesozoic, non-marine conglomeratic sequences of northern Antarctic Peninsula Cthe Botany Bay Group). British Antarctic Survey, Bulletin, 65, 1±32. ÐÐ HAMER, R. D. and INESON, J. R. 1984. Proximal volcaniclastic sedimentation in a Cretaceous back-arc basin, northern Antarctic Peninsula. 219±229. In KOKELAAR, B. P. and HOWELLS, M. F. Ceds). Marginal basin geology. Geological Society, London, Special Publication, 16, 322 pp. FEISTMANTEL, O. 1877. Jurassic CLiassic) ¯ora of the Rajmahal Group, in the Rajmahal Hills. Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 2, 1, 1±110. ÐÐ 1878±1879. PalaÈozoische und mesozoische Flora des ostlichen Australiens. Palaeontographica, Supplement, 3, 53±130, pls 1±18 C1878); 133±195, pls 19±30 C1879). ÐÐ 1890. Geological and palaeontological relations of the coal and plant-bearing beds of Palñozoic and Mesozoic age in eastern Australia and Tasmania: with special reference to the fossil ¯ora. Memoirs of the Geological Survey of New South Wales, Palaeontology, 3, 186 pp., 30 pls. FERUGLIO, E. 1937. Dos nuevas especies de Hausmannia de la Patagonia. Notas del Museo de La Plata VPaleontologie), 2, 125±136. FLORIN, R. 1940. The Tertiary fossil conifers of South Chile and their phytogeographical signi®cance, with a review of the fossil conifers of southern lands. Kungliga Svenska Vetenskapsakademie Handlingar, Serie 3, 19 C2), 1±107. FONTAINE, W. M. 1889. The Potomac or Younger Mesozoic ¯ora. Monographs of the United States Geological Survey, 15, 1±377, 180 pls. FRANCIS, J. E. 1986. Growth rings in Cretaceous and Tertiary wood from Antarctica and their palaeoclimatic implications. Palaeontology, 29, 665±684. FRENGUELLI, J. 1941. Sagenopteris y Linguifolium del Lias de Piedra Pintada en el NeuqueÂn CPatagonia). Notas Museo de La Plata, SeccioÂn Paleontologia, 34, 404±437. ÐÐ 1943. ResenÄa crõÂtica de los geÂneros atribuõÂdos a la `Serie de Thinnfeldia'. Revista del Museo de La Plata, SeccioÂn Paleontologia, 2, 225±342. ÐÐ 1944. La ¯oÂrula de la base de la `Serie de Cacheuta' en el Cerro de los BanÄos, Mendoza. Notas Museo de La Plata, SeccioÂn Paleontologia, 63, 271±310. ÐÐ 1947. El genero `Cladophlebis' y sus representantes en la Argentina. Anales de la Museo de La Plata, n.s., SeccioÂn Paleontologia B, 2, 5±74. ÐÐ 1949. Los estratos con Estheria en el Chubut CPatagonia). Revista de la AsociacioÂn GeoloÂgica Argentina, 4, 11±24. FUJIAN PROVINCE BUREAU OF GEOLOGY AND MINERAL RESOURCES 1985. Regional geology of Fujian Province. People's Republic of China, Ministry of Geology and Mineral Resources, Beijing, 671 pp. [In Chinese, English summary]. GEE, C. T. 1989. Revision of the Late Jurassic/Early Cretaceous ¯ora from Hope Bay, Antarctica. Palaeontographica, Abteilung B, 213, 149±214. GIDDY, C. 1974. Cycads of South Africa. Purnell and Sons, Capetown, 122 pp. GOTHAN, W. 1912. UÈ ber die Gattung Thinnfeldia Ettingshausen. Abhandlungen der Naturhistorischen Gesellschaft zu NuÈrenburg, 19, 67±80. GOULD, R. E. 1968. Morphology of Equisetum laterale Phillips, 1829, and E. bryanii sp. nov. from the Mesozoic of south-eastern Queensland. Australian Journal of Botany, 16, 153±176.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 86 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2

GUANGDONG PROVINCE BUREAU OF GEOLOGY AND MINERAL RESOURCES 1988. Regional geology of Guangdong Province. People's Republic of China, Ministry of Geology and Mineral Resources, Beijing, 941 pp. [In Chinese, English summary]. HALLE, T. G. 1910. On the Swedish species of Sagenopteris Presl and on Hydropterangium nov. gen. Kungliga Svenska Vetenskapsakademie Handlingar, 45 C7), 1±16. ÐÐ 1913. The Mesozoic ¯ora of Graham Land. Wissenschaftliche Ergebnisse der Schwedischen SuÈdpolar- Expedition 1901±1903, 3 C14), 123 pp. HARRIS, T. M. 1932. The fossil ¯ora of Scoresby Sound, East Greenland. Meddelelser om Grùnland, 85, 1±133. ÐÐ 1946. Liassic and Rhaetic plants collected in 1936±38 from East Greenland. Meddelelser om Grùnland, 114 C9), 1±38. ÐÐ 1961. The Yorkshire Jurassic ¯ora. I. Thallophyta, Pteridophyta. British Museum CNatural History), London, 212 pp. ÐÐ 1962. The occurrence of the fructi®cation Carnoconites in New Zealand. Transactions of the Royal Society of New Zealand VGeology), 1, 17±27. ÐÐ 1964. The Yorkshire Jurassic ¯ora. II. Caytoniales, Cycadales and pteridosperms. British Museum CNatural History), London, 191 pp. ÐÐ 1969. The Yorkshire Jurassic ¯ora. III. Bennettitales. British Museum CNatural History), London, vi ‡ 186 pp., 7 pls. ÐÐ 1979. The Yorkshire Jurassic ¯ora. V. Coniferales. British Museum CNatural History), London, 166 pp., 7 pls. ÐÐ 1980. The Yorkshire Jurassic fern Phlebopteris braunii CGoeppert) and its reference to Matonia R. Br. Bulletin of the British Museum VNatural History), Geology Series, 33, 295±311. HENKEL, J. B. and HOCHSTETTER, W. C. 1865. Synopsis der NadelhoÈlzer. J. G. Cottasch, Stuttgart, xxviii ‡ 446 pp. HERBST, R. 1960. Descripcion de ejemplares fertiles de Hausmannia CProtorhipis) papilio Feruglio, procedentes de los Estratos de Baquero CSanta Cruz). Acta Geologica Lilloana, 3, 227±232. ÐÐ 1964a. La ¯ora liaÂsica de C. Meschio, Provincia de Chubut, Argentina. Ameghiniana, 3, 227±234. ÐÐ 1964b. La ¯ora liaÂsica de la zona del RõÂo Atuel, Mendoza, Argentina. Revista de la AsociacõÂon GeoloÂgica Argentina, 19, 108±131. ÐÐ 1965. La ¯ora foÂsil de la FormacioÂn Roca Blanca, Provincia Santa Cruz, Patagonia, con consideraciones geoloÂgicas y estratigra®cas. Opera Lilloana, TucumaÂn, 12, 1±101. ÐÐ 1966. RevisioÂn de la ¯ora liaÂsica de Piedra Pintada, Provincia de NeuqueÂn, Argentina. Revista del Museo de La Plata, n.s., Seccion Paleontologia, 30, 27±53. ÐÐ 1968. Las ¯oras liaÂsicas argentinas con consideraciones estratigra®cas. Actas, Jornadas Geologicas Argentinas, 3, 145±162. ÐÐ 1971. Palaeophytologia Kurtziana. III. 7. Revision de las especies argentinas del genero Cladophlebis. Ameghiniana, 8, 265±281. ÐÐ 1975. Consideraciones sobre las Dipteridaceae CFilices) del Gondwana. Actas, I Congreso Argentino de Paleontologia y Bioestratigra®a, TucumaÂn, Argentina, 1, 525±535. ÐÐ 1979. Review of the Australian Dipteridaceae. Proceedings of the Linnean Society of New South Wales, 103, 7±21. ÐÐ 1993. Dipteridaceae CFilicales) del Triasico del Arroyo Llantenes CProvincia de Mendoza) y de Paso Flores CProvincia del NeuqueÂn), Argentina. Ameghiniana, 30, 155±162. ÐÐ and ANZOTEGUI, L. M. 1968. Nuevas plantas de la ¯ora del juraÂsico medio Cmatildense) de TaquetreÂn, Provincia de Chubut. Ameghiniana, 5, 183±190. HOLMES, W. B. K. 1982. The Middle Triassic ¯ora from Benolong, near Dubbo, central-western New South Wales. Alcheringa, 6, 1±33. HUBEI PROVINCE BUREAU OF GEOLOGY AND MINERAL RESOURCES 1990. Regional geology of Hubei Province. People's Republic of China, Ministry of Geology and Mineral Resources, Beijing, 705 pp. [In Chinese, English summary]. IWAI, J., HONGNUSONTHI, A., ASAMA, K., KOBAYASHI, T., KONNO, E., NAKORNSRI, N., VEERABURAS, M. and YUYEN, W. 1975. Non-marine Mesozoic formations and fossils in Thailand and Malaysia. 191±218. In KOBAYASHI, T. and TORIYAMA, R. Ceds). Geology and palaeontology of Southeast Asia, 15. University of Tokyo Press, Tokyo. JEFFERSON, T. H. 1981. Palaeobotanical contributions to the geology of Alexander Island, Antarctica. Unpublished PhD thesis, University of Cambridge, 265 pp. JOHNSTON, R. 1894. Notes on some fossil plants new to Tasmania. Part I. Papers and Proceedings of the Royal Society of Tasmania, 1893, 170±178, 2 pls. ÐÐ 1896. Notes on some fossil plants new to Tasmania. Part II. Papers and Proceedings of the Royal Society of Tasmania, 1894±5, 57±63, 1 pl.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 87

JONES, D. L. 1993. Cycads of the world: ancient plants in today's landscape. Smithsonian Institution Press, Washington, DC, 312 pp. KIMURA, T. 1976. Mesozoic plants from the Yatsushiro Formation CAlbian), Kumamoto Prefecture, Kyushu, southwest Japan. Bulletin of the National Science Museum, Series C VGeology), 2, 179±208. ÐÐ and SEKIDO, S. 1971. Ctenis species from the Itoshiro Sub-Group CLower Cretaceous), the Tetori Group, central Honshu, Japan. Transactions and Proceedings of the Palaeontological Society of Japan, New Series, 86, 360±368, pls 44±45. KONIJNENBURG-van CITTERT, J. H. A. van 1993. A review of the Matoniaceae based on in situ spores. Review of Palaeobotany and Palynology, 78, 235±267. LACEY, W. S. and LUCAS, R. C. 1981. The Triassic ¯ora of Livingston Island, South Shetland Islands. British Antarctic Survey, Bulletin, 53, 157±173. LINNAEUS, C. 1753. Species plantarum. L. Salvii, Stockholm, 1200 ‡ 30 pp. C2 volumes). LUNDBLAD, A. B. 1950. Studies in the Rhaeto-Liassic ¯oras of Sweden. I. Pteridophyta, pteridospermae, and cycadophyta from the mining district of NW Scania. Kungliga Svenska Vetenskapsakademie Handlingar, 1 C8), 1±82. MACDONALD, D. I. M., BARKER, P. F., GARRETT, S. W., INESON, J. R., PIRRIE, D., STOREY, B. C., WHITHAM, A. G., KINGHORN, R. R. F. and MARSHALL, J. E. A. 1988. A preliminary assessment of the hydrocarbon potential of the Larsen Basin, Antarctica. Marine and Petroleum Geology, 5, 34±53. MCDOUGALL, I. and MCELHINNY, M. W. 1970. The Rajmahal Traps of India ± K-Ar ages and palaeomagnetism. Earth and Planetary Science Letters, 9, 371±378. MAHESHWARI, H. K. 1986. Thinnfeldia indica Feistmantel and associated plant fossils from Tiruchirapalli District, Tamil Nadu. Palaeobotanist, 35, 13±21. ÐÐ and SINGH, N. P. 1976. On some plant fossils from the Pariwar Formation, Jaisalmer Basin, Rajasthan. Palaeobotanist, 23, 116±123. MENE NDEZ, C. A. 1956. FloÂrula JuraÂsica del Bajo de los Baguales en Plaza Huincul, NeuqueÂn. Acta Geologica Lilloana, 1, 315±338. MICHAUX, A. 1803. Flora boreali-americana, 2. C. Crapelet and F. Levrault, Paris and Strasbourg, iii ‡ 340 pp., pls 30±51. MILLAR, I. L., MILNE, A. J. and WHITHAM, A. G. 1990. Implications of Sm-Nd garnet ages for the stratigraphy of northern Graham Land, Antarctic Peninsula. Zentrallblatt fuÈr Geologie und PalaÈontologie, 1, 97±104. MOÈ LLER, H. J. and HALLE, T. G. 1913. The fossil ¯ora of the coal-bearing deposits of south-eastern Scania. Arkiv fuÈr Botanik, 13 C7), 1±45. MOREL, E. M., ARTABE, A. E., GANUZA, D. G. and BREA, M. 1994. Las plantas fosiles de la formacion Monte Flora, en Bahia Botanica, Peninsula Antartica. I. Dipteridaceae. Ameghiniana, 31, 23±31. NATHORST, A. G. 1907. On the Upper Jurassic ¯ora of Hope Bay, Graham Land. Compte Rendus, 10th International Geological Congress, Mexico, 1906, 10, 1269±1270. NEWELL, S. J. 1989. Variation in lea¯et morphology among populations of Caribbean cycads CZamia). American Journal of Botany, 76, 1518±1523. Oà ISHI, S. 1932. The Rhaetic plants from the Nariwa district, Prov. Bitchuà COkayama Prefecture), Japan. Journal of the Faculty of Science, Hokkaido University, Series 4, 1, 257±380. ÐÐ and YAMASITA, K. 1936. On the fossil Dipteridaceae. Journal of the Faculty of Science, Hokkaido University, Series 4, 3, 135±184. OLDHAM, T. and MORRIS, J. 1862. Fossil ¯ora of the Rajmahal Series, Rajmahal Hills, Bengal. Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 2, 1, 1±52. OLIVER, P. J., CAMPBELL, J. D. and SPEDEN, I. G. 1982. The stratigraphy of the Torlesse rocks of the Mt Somers area CS81), Mid-Canterbury. Journal of the Royal Society of New Zealand, 12, 243±271. PANKHURST, R. J. 1982. Rb-Sr geochronology of Graham Land, Antarctica. Journal of the Geological Society of London, 139, 701±711. PANT, D. D. and SRIVASTAVA, G. K. 1968. On the cuticular structure of Araucaria CAraucarites) cutchensis CFeistmantel) comb. nov. from the Jabalpur series, India. Botanical Journal of the Linnean Society, 61, 201±206. PERSON, C. P. and DELEVORYAS, T. 1982. The Middle Jurassic ¯ora of Oaxaca, Mexico. Palaeontographica, Abteilung B, 180, 82±119. PETRIELLA, B. and ARRONDO, O. G. 1984. La tafo¯oÂrula liaÂsica de Estancia La Juanita, Provincia de Santa Cruz, Argentina. Ameghiniana, 21, 35±41. PHILLIPS, J. 1829. Illustrations of the geology of Yorkshire: or a description of the strata and organic remains of the Yorkshire coast. York, xvi ‡ 192 pp., 36 pls. POOLE, I. and CANTRILL, D. J. 2001. Fossil woods from Williams Point Beds, Livingston Island, Antarctica: a Late Cretaceous southern high latitude ¯ora. Palaeontology, 44, 1081±1112.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN 88 S P E C I A L P A P E R S I N P A L A E O N T O L O G Y , 7 2

PRESL, K. B. 1847. Die GefassbuÈndel im Stipes der Farrn. Haase, Prague, i ‡ 48 pp. PYRAH, B. J. 1979. Catalogue of type and ®gured fossils in the Yorkshire Museum: Part 4. Proceedings of the Yorkshire Geological Society, 42, 415±437. RAO, A. R. 1953. Some observations on the Rajmahal ¯ora. Palaeobotanist, 2, 25±28. RAO, R., XU, J., CHEN, Y. and ZOU, D. 1987. The Triassic System of Qinghai-Xizang Plateau. Geological Memoirs, People's Republic of China Ministry of Geology and Mineral Resources, 2 C7), 1±239. REES, P. M. 1990. Palaeobotanical contributions to the Mesozoic geology of the northern Antarctic Peninsula region. Unpublished PhD thesis, University of London, 285 pp. ÐÐ 1993a. Dipterid ferns from the Mesozoic of Antarctica and New Zealand and their stratigraphical signi®cance. Palaeontology, 36, 337±356. ÐÐ 1993b. Caytoniales in Early Jurassic ¯oras from Antarctica. Geobios, 26, 33±42. ÐÐ 1993c. Revised interpretations of Mesozoic palaeogeography and volcanic arc evolution in the northern Antarctic Peninsula region. Antarctic Science, 5, 77±85. ÐÐ 1993d. Mesozoic ¯oras from the northern Antarctic Peninsula. Comptes Rendus de l'AcadeÂmie des Sciences, SeÂrie II, 316, 1651±1657. ÐÐ and CLEAL, C. J. 1993. Marked polymorphism in Archangelskya furcata, a pteridospermous frond from the Jurassic of Antarctica. Special Papers in Palaeontology, 49, 85±100. ÐÐ and SMELLIE, J. L. 1989. Cretaceous angiosperms from an allegedly Triassic ¯ora at Williams Point, Livingston Island, South Shetland Islands. Antarctic Science, 1, 239±248. ÐÐ ZIEGLER, A. M. and VALDES, P. J. 2000. Jurassic phytogeography and climates: new data and model comparisons. 297±318. In HUBER, B. T., MACLEOD, K. G. and WING, S. L. Ceds). Warm climates in earth history. Cambridge University Press, 480 pp. ÐÐ ÐÐ GIBBS, M. T., KUTZBACH, J. E., BEHLING, P. J. and ROWLEY, D. B. 2002. Permian phytogeographic patterns and climate data/model comparisons. Journal of Geology, 110, 1±31. REMANE, J., CITA, M. B., DERCOURT, J., BOUYSSE, P., REPETTO, F. L. and FAURE-MURET, A. 2002. International stratigraphic chart. International Union of Geological Sciences, Paris. RILEY, T. R. and LEAT, P. T. 1999. Large volume silicic volcanism along the proto-Paci®c margin of Gondwana: lithological and stratigraphical investigations from the Antarctic Peninsula. Geological Magazine, 136, 1±16. SAHNI, B. 1928. Revision of the Indian fossil plants. Part I. Coniferales. Ca) Impressions and incrustations. Memoirs of the Geological Survey of India, Palaeontologica Indica, New Series, 11, 1±49. ÐÐ and RAO, A. R. 1933. On some Jurassic plants from the Rajmahal Hills. Journal and Proceedings of the Asiatic Society of Bengal, New Series, 27, 183±208. SAPORTA, G. 1873±1875. PaleÂontologie francËaise ou description des fossiles de la France. 2, VeÂgeÂtaux, Plantes Jurassiques. Paris. Vol. 1 C1873), 506 pp., pls 1±70; Vol. 2 C1875), 352 pp., pls 71±127. SCHENK, A. 1871. BeitraÈge zur Flora der Vorwelt, IV. Die Flora der nordwestdeutschen Wealdenformation. Palaeontographica, 19, 201±276. SCHIMPER, W. P. 1869. Traite de paleÂontologie veÂgeÂtale, I. J. B. BaillieÁre, Paris, iv ‡ 740 pp. SCHWEITZER, H.-J., KONIJNENBURG-van CITTERT, J. H. A. van and BURGH, J. van der 1997. The Rhaeto-Jurassic ¯ora of Iran and Afghanistan. 10. Bryophyta, Lycophyta, Pterophyta ± Eusporangiatae and ± Protoleptosporangiatae. Palaeontographica, Abteilung B, 243, 103±192. SENGUPTA, S. 1988. Upper Gondwana stratigraphy and palaeobotany of Rajmahal Hills, Bihar, India. Memoirs of the Geological Survey of India, Palaeontologia Indica, New Series, 68, 1±182. SEWARD, A. C. 1894. Catalogue of the Mesozoic plants in the Department of Geology, British Museum VNatural History). The Wealden ¯ora, Part I. Thallophyta-Pteridophyta. British Museum CNatural History), London, xl ‡ 179 pp. ÐÐ 1900. Catalogue of the Mesozoic plants in the Department of Geology, British Museum VNatural History). The Jurassic ¯ora. I. The Yorkshire coast. British Museum CNatural History), London, xii ‡ 341 pp. ÐÐ 1911. The Jurassic ¯ora of Sutherland. Transactions of the Royal Society of Edinburgh, 47, 643±709. ÐÐ 1931. Plant life through the ages. University Press, Cambridge, xxi ‡ 603 pp. ÐÐ and DALE, E. 1901. On the structure and af®nities of Dipteris, with notes on the geological history of the Dipteridinñ. Philosophical Transactions of the Royal Society of London, Series B, 194, 487±513. SHAH, S. C., SINGH, G. and GURURAJA, M. N. 1973. Observations on the post-Triassic Gondwana sequence of India. Palaeobotanist, 20, 221±237. SHARMA, B. D. 1969. On Pentoxyleae remains from Amarjola in the Rajmahal Hills, India. Ameghiniana, 6, 50±56. SHUYING, D. 1987. The Jurassic ¯ora of Zhaitang, western hills of Beijing. Unpublished Doctoral dissertation, University of Stockholm, 95 pp.

Palaeontology SP72 PALA 110841 DISK SR 12/7/4 15:09 ALDEN R E E S A N D C L E A L : L O W E R J U R A S S I C F L O R A S F R O M A N T A R C T I C A 89

SICHUAN STRATIGRAPHIC GROUP 1976. The stratigraphic tables of Sichuan. Geology Press, Beijing, 669 pp. [In Chinese]. STERNBERG, K. M. von 1838. Versuch einer geognostisch-botanischen Darstellung der Flora der Vorwelt. Volume II V7±8). G. HaÈsse und SoÈhne, Prague, pp. 81±220. STIPANICIC, P. N. and BONETTI, M. I. R. 1970. Posiciones estratigra®cas y edades de las principales ¯oras juraÂsicas argentinas. II. Floras doggerianas y maÂlmicas. Ameghiniana, 7, 101±118. STRZELECKI, P. E. de 1845. Physical description of New South Wales and Van Diemans Land. Longman, Brown and Green, London, xix ‡ 462 pp., 19 pls, 1 map. THOMAS, H. H. 1925. The Caytoniales, a new group of angiospermous plants from the Jurassic rocks of Yorkshire. Philosophical Transactions of the Royal Society of London, Series B, 213, 299±363, pls 11±25. THOMSON, M. R. A. 1981. Late Mesozoic stratigraphy and invertebrate palaeontology of the South Orkney Islands. British Antarctic Survey, Bulletin, 54, 65±83. ÐÐ PANKHURST, R. J. and CLARKSON, P. D. 1983. The Antarctic Peninsula ± a late Mesozoic±Cenozoic arc Creview). 289±294. In OLIVER, R. L., JAMES, P. R. and JAGO, J. B. Ceds). Antarctic earth science. Australian Academy of Science and Cambridge University Press, Canberra and Cambridge, 697 pp. TIDWELL, W. D., KIM, J. H. and KIMURA, T. 1987. Mid-Mesozoic leaves from near Ida Bay, southern Tasmania, Australia. Papers and Proceedings of the Royal Society of Tasmania, 121, 159±170. TOWNROW, J. A. 1958. On Dicroidium, probably a pteridospermous leaf, and other leaves now removed from this genus. Transactions of the Geological Society of South Africa, 60, 21±60, 3 pls. ÐÐ 1967a. Fossil plants from Allan and Carapace Nunataks, and from the Upper Mill and Shackleton glaciers, Antarctica. New Zealand Journal of Geology and Geophysics, 10, 456±473. ÐÐ 1967b. The Brachyphyllum crassum complex of fossil conifers. Papers and Proceedings of the Royal Society of Tasmania, 101, 149±172. VAKHRAMEEV, V. A. 1991. Jurassic and Cretaceous ¯oras and climates of the Earth. Cambridge University Press, Cambridge, xx ‡ 318 pp. VALLE, R. A. del and FOURCADE, N. H. 1986. La cuenca sedimentaria pos-triaÂsica del extremo nororiental de la penõÂnsula AntaÂrtica. Contribuciones Cientõ®cas del Instituto AntaÂrtico Argentino, 323, 1±24. VISHNU-MITTRE 1957. Studies on the fossil ¯ora of Nipania CRajmahal Series) India ± Pentoxyleae. Palaeobotanist, 6, 31±46. VOLKHEIMER, W. 1968. Esporas y granos de polen del JuraÂsico de NeuqueÂn CRepublica Argentina). I. Descripciones sistemaÂticas. Ameghiniana, 5, 333±370. ÐÐ 1969. Esporas y granos de polen del JuraÂsico de NeuqueÂn CRepublica Argentina). II. Asociaciones micro- ¯orõÂsticas, aspectos paleoecoloÂgicos y paleoclima. Ameghiniana, 6, 127±145. WALKOM, A. B. 1917. Mesozoic ¯oras of Queensland. Part 1 ± concluded. The ¯ora of the Ipswich and Walloon series. Cd) Ginkgoales, Ce) Cycadophyta, Cf) Coniferales. Publications of the Geological Survey of Queensland, 259, 1±49. WALTER, H. 1985. Vegetation of the Earth and ecological systems of the biosphere. Springer, New York, 318 pp. WARD, L. F. 1900. Status of Mesozoic ¯oras of the United States, First paper: The older Mesozoic. Reports of the United States Geological Survey, 20, 211±748. WATSON, J. 1969. A revision of the English Wealden ¯ora, I Charales ± Ginkgoales. Bulletin of the British Museum VNatural History), Geology Series, 17, 210±254, pls 1±6. ÐÐ and BATTEN, J. 1990. A revision of the English Wealden ¯ora, II. Equietales. Bulletin of the British Museum VNatural History), Geology Series, 46, 37±60. WEGENER, A. 1915. Die Entstehung der Kontinente und Ozeane. Vieweg, Braunschweig, 135 pp. WHITE, M. E. 1981. Revision of the Talbragar Fish Bed Flora CJurassic) of New South Wales. Record of the Australian Museum, 33, 695±721. WU, X. W. 1982. Late Triassic plants from eastern Xizang. Paleontology of Tibet, 5, 63±103. YUNNAN STRATIGRAPHIC GROUP 1976. The stratigraphic tables of Yunnan. Geology Press, Beijing, 437 pp. [In Chinese]. ZEBA±BANO, MAHESHWARI, H. K. and BOSE, M. N. 1979. Some plant remains from Pathargama, Rajmahal Hills, Bihar. Palaeobotanist, 26, 144±156. ZHEJIANG STRATIGRAPHIC GROUP 1979. The stratigraphic tables of Zhejiang. Geology Press, Beijing, 161 pp. ZIEGLER, A. M. 1990. Phytogeographic patterns and continental con®gurations during the Permian Period. 363±379. In MCKERROW, W. S. and SCOTESE, C. R. Ceds). Palaeozoic palaeogeography and biogeography. Geological Society, London, Memoir, 12, 435 pp.

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P. MCA. REES Department of Geosciences University of Arizona Tucson AZ 85721, USA e-mail [email protected]

C. J. CLEAL Department of Biodiversity and Systematic Biology National Museums and Galleries of Wales Cathays Park Cardiff CF10 3NP, UK e-mail [email protected]

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