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https://doi.org/10.24199/j.mmv.1977.38.03 4 April 1977

GASTROPODS FROM SOME EARLY DEVONIAN LIMESTONES OF THE WALHALLA SYNCLINORIUM, CENTRAL By C. B. Tassell Albany Residency Museum, Port Road, Albany, W.A. Abstract

Seventeen gastropods from Devonian limestones at Marble Creek (also known as Toon- gabbie), and Loyola within the Walhalla synclinorium are described. These include four new forms: Platyceras (Platyceras) mansfieldense and P. (Praenatica) sp. A. from Loyola, and P. {Platyceras) sp. A. and P. (Orthonychia) sp. A. from Marble Creek. The other described forms are all platyceratids except Tremanotus cyclocostatus and Michelia sp. from Marble Creek, Oriostoma sp. n., and an indeterminate turbiniform gastropod from Deep Creek and Scalaetrochus lindstromi from Loyola. Tropidodiscus centrifugalis and ITemnodiscus pharetroides from the mudstones at Loyola are also redescribed. The gastropod faunas of the limestones are dominated by coprophagic platyceratid gastropods and constitute further examples of this widely known crinoid-gastropod association.

Introduction Gastropods from the Toongabbie Limestone, The limestone deposits along the eastern Marble Creek, were first noted by McCoy who limb of the Walhalla synclinorium each consist observed 'some traces of Gasteropoda, appar- of a number of small lenses of limestone. The ently of the genus Acroculia, too imperfect to determination possible, and a fragment deposits extend about 120 km from Loyola in render of Chap- the north, about 130 km north-east of Mel- Bellerophort Murray (1878, p. 49). Nisa (Veto- bourne, to Marble Creek in the south, about man (1907) noted the presence of brazieri Etheridge and Trochus (Scalae- 140 km east of . The limestone at tuba) trochus) sp. In 1916 he noted Tremanotus Loyola was the first to be noted in print. Selwyn pritchardi Cresswell and Coelocaulus brazieri and Ulrich (1867, p. 35) provided a chemical (Etheridge) described Diaphorostoma analysis of a 'white limestone from near Mans- and incisitm. field'. The first note of fossils appears to be that of McCoy, who considered the limestone Talent and Philip (1956), when describing to be Palaeozoic and was quoted to this effect the gastropod fauna from Marble Creek, by Couchman (1877, p. 19). Chapman (1914) erected two new genera, Ostlerina and Cow- mentioned an unidentified form of gastropod warrella. They also described eight new species and in 1916 he described two gastropods from and mentioned three poorly known forms. the Loyola Limestone, Platyceras cornutum These two new genera were subsequently Hisinger and Orthonychia brevis Chapman. synonymized by Knight et ah ( 1960) However, the latter is one of the nautiloids The lack of work both locally and inter- which are quite common at Loyola. He also nationally on Middle Palaeozoic gastropod described two species of gastropods from the faunas makes comparison with assemblages of associated mudstones, Temnodiscus phare- similar age difficult, and has also resulted in a troides and Euomphalus centrifugalis. Since number of genera being used in a very wide then no further work on the gastropod fauna sense. As a result of the lack of definition of has been undertaken. generic limits, the species described here are The limestone deposit with the least known compared with the type species as well as other south-eastern . fauna is that at Deep Creek, about 6 km east species from following abbreviations of Walhalla. Together with the limestone at In this study the Marble Creek (also known as Toongabbie), have been used: National of Victoria Palaeonto- it appears to have been first noted by Murray P, Museum Collection; (1878, p. 48). The only mention of a gastro- logical , Melbourne University Geology pod from this locality is by Chapman (1916) M.U.G.D. who described Platyceras minutum. Department;

231 232 C. B. TASSELL

G.S.V., Geological Survey of Victoria Collec- by Philip (1974). He discussed the current tion, now housed in the National Museum uncertainty in correlations between the dif- of Victoria. ferent facies of the Lower Devonian stages in All measurements are in millimetres and the Europe. Because of this present uncertainty, following symbols relating to the measurements their application in Australia should not be have been used: dogmatic. The gastropod Hap, height of aperture; Ht, total height of evidence for age determin- ations at Loyola is shell; L, length measured at the selenizone in minimal. Scalaetrochus lindstromi the bellerophontids; Lap, length of aperture; occurs at both Lilydale and Loyola. It is generally Wap, width of aperture; Wh, total number of considered that the Lilydale Limestone whorls in shell; Wit, width at last trema; Wt, is Late Siegenian (Strusz, 1972). total width of shell; *, specimen incomplete. However, the only other known occurrence of this genus is Scalaetrochus fragosus from the Acknowledgements Middle Devonian Anderdon Limestone, On- tario, Canada (Linsley, 1968). I wish to thank Mr T. A. Darragh, of the Within the mudstone surrounding the lime- National Museum of Victoria, Melbourne, for stone lenses at Loyola, Straparollus his discussion and criticism of this work; Dr O. (Strapa- rollus) serpenteus Talent and P. Singleton and Dr P. J. Coleman for their Loxonema sp. nov. of Talent occur. helpful comments, criticisms and discussions; (1963) These gastropods were originally Mr M. Cooper, of the University of Melbourne, described from the Kilgower Member, Tabberabbera Geology Department, for the loan of type by Talent (1963). This unit was considered specimens; Margaret Tassell for the photo- by Strusz (1972) to be Late Siegenian-Emsian in graphs and discussion throughout this study. age. Palaeoecology Age of the faunas The limestone at Marble Creek is composed As knowledge of Middle Palaeozoic gastro- largely of crinoidal fragments together with a pods is limited, they do not contribute signifi- few corals and stromatoporoids. In comparison cantly towards age determinations of the with the crinoids and coelenterates the other limestones. In this instance the situation is faunal elements comprise only a small per- further aggravated by the domination of centage of the fauna. These minor elements Platyceratids in each of the gastropod faunas. include gastropods, bivalves, nautiloids, rostro- Most discussions about the age of the lime- conchians (notably Conocardium), brachiopods stones at Marble Creek and Deep Creek have and trilobites. This faunal abundance and usually considered them to be of the same age. diversity is in complete contrast to that of the This is supported by the presence of the dis- surrounding mudstones which are virtually tinctive Platyceras (Visitator) cylindricum at unfossiliferous (Talent, 1956). both localities. Strusz (1972) assessed the The commensal relationship between the available information from both these localities coprophagic gastropods of the family Platy- and considered them to be Late Siegenian. ceratidae and crinoids has been known for a The age of the Loyola Limestone has been long time. Lane (1973) described in detail argued for some time. Most recently Cooper such a relationship from the Carboniferous of (1973) noted the presence of a polygnathan Indiana. At Marble Creek the disarticulated conodont element in the fauna and considered nature of the crinoid crowns implies some post- the limestone to be Early Emsian. This age mortem transport. Although the gastropod determination has been accepted by other fauna at Marble Creek is dominated by mem- workers (Strusz, 1972; Vandenberg et a/., bers of the Platyceratidae, none have been 1976). found in situ on a crinoid crown. Discussion of the ages of these limestones Apart from the dominant platyceratids, the must be placed in the perspective of comments gastropod fauna from Marble Creek is limited. GASTROPODS FROM WALHALLA SYNCLINORIUM 233

Tremanotus cyclocostatus is considerably tinct bodies of limestone interbedded with the smaller than T. pritchardi from the Lilydale surrounding highly fossiliferous mudstones Limestone of comparable age. Also present (Cooper, 1973). This limestone exhibits a are poorly preserved specimens of Michelia sp. great deal more variation in composition than Again considerably larger forms are known the limestones from Deep Creek and Marble from both the Lilydale Limestone and the Creek. In part it is composed largely of slightly younger limestone at Taemas, N.S.W. crinoidal material only slightly disarticulated. Chapman (1907) noted the presence at Marble Coelenterates dominate the limestone in other Creek of Scalaetrochus sp. but this specimen areas. has not been relocated. The total fauna of the limestones is diverse

The gastropod fauna of the Toongabbie but the gastropod component is quite limited Limestone is markedly different from the only being represented by only a few species. How- other adequately known Lower Devonian ever, there is no tendency at Loyola towards gastropod fauna from Victoria, that of the reduction in size; rather the platyceratids from Lilydale Limestone. This latter fauna from a this limestone are comparable in size to, or protected shallow marine environment is larger than, those from Marble Creek. dominated by large gastropods, both high- The low gastropod diversity of the lime- spired and planispiral (Tassell, 1976). Signi- stones is in marked contrast to the gastropod ficantly, no coprophagic gastropods are known fauna of the associated mudstones. Chapman from this limestone. Also this limestone is not (1916) described from the mudstones ? Tem- dominated by crinoidal fragments. nodiscus pharetroides and Tropidodiscus The limestones at Deep Creek differ in centrifugalis as well as noting Platyceras composition from those at Marble Creek in a cornutum. Straparollus {Straparollus) serpen- number of ways. They are not dominated by teus Talent and Loxonema sp. nov. of Talent crinoidal remains; rather, corals comprise the 1963 also occur in the mudstones. major biological component of the limestone. The minor components of the Marble Creek Systematic descriptions fauna are considerably more important con- Family BELLEROPHONTIDAE McCoy, stituents of the Deep Creek Limestone. This is 1851 so particularly of bryozoa, ostracods and brachiopods. Other minor components include Subfamily TROPIDODISCINAE Knight, trilobites, algae, rostroconchians, bivalves and 1956 gastropods. Genus Tropidodiscus Meek and Worthen, The total fauna at Deep Creek is as diverse 1866 as the faunas from both Marble Creek and Type Species: Tropidodiscus curvilineatus Loyola. But the gastropod fauna, dominated (Conrad), 1842; Lower Devonian; Schoharie, by platyceratids, is noticeably less diverse. In New York, U.S.A. the case of the coprophagic platyceratids, this Tropidodiscus centrifugalis (Chapman), 1916 may be a reflection of the limited number, or diversity, of the crinoids. Not only is the gas- (Plate figure tropod fauna of restricted diversity, it is also 7, 5) composed only of small forms. The most 1916 Euomphalus centrifugalis Chapman, pp. 89, pi. figs. 30-31, pi. figs. 54-55. abundant gastropod P. (P.) minutum rarely 101, 4, 6, Small form exceeds 5 mm in diameter. P. (F.) cylindricum Diagnosis: of genus with foliaceous growth lines that vary slightly during at Deep Creek is smaller in all cases than growth are moderately widely members of that species at Marble Creek. An and spaced. explanation of such apparent dwarfing is not Description: Small to medium-sized form with readily apparent, particularly as none of the prominent angular dorsal crest; whorl profile other faunal elements exhibits such a tendency. gently rounded from the angular dorsal crest the umbilici, The limestone at Loyola consists of four dis- to the edge of then rounded more :

234 C. B. TASSELL

strongly; umbilici moderately deep and wide; ? Temnodiscus pharetroides Chapman aperture not greatly expanded, sub-triangular (Plate 3, figure 1) in shape; parietal lip probably thin, with high 1916 Temnodiscus pharetroides Chapman, ridge formed by dorsal angulation of preceding p. 78, pi. 2, figs. 4-5, pi. 6, figs. 50-51. whorl; outer lip with a deep v-shaped sinus Description: Small planispiral form with a dis- culminating at the dorsal angulation in a tinctive dorsal crest; whorl profile from angular narrow slit that probably produces a narrow dorsal crest moderately curved to edge of selenizone; shape of outer lip slightly variable umbilici where it is rounded more strongly into throughout growth; selenizone details unknown; the umbilici aperture flared, sub-ovoidal in collabral lines moderately widely spaced, shape; final whorl expanded, whorls few in tendency to be foliaceous. number; other details unknown because of poor Dimensions (in mm) preservation. L Wh PI 2844 I3.7 5 Dimensions: P12845 9-1 4 P41828 L Ht Wt 12-1 5 P12835 71 6-6 4-2 Location Types: of National Museum of Vic- Location of Types: National Museum of Vic- toria. Holotype, P12844. Paratype, P12845. toria. Holotype, P12835. Type Locality: Chapman designated the holo- Type Locality: Loyola. type as the specimen from Killara and the Material: Holotype. paratype as the specimen from Loyola. In his Discussion: The holotype is an internal plate explanation (p. 101) this situation is mould which shows reversed with the Loyola specimen being clearly a dorsal crest; otherwise there designated as the holotype. The specimen from is little diagnostic information. The assignment by Loyola is both an external mould and internal Chapman of this single speci- men to the genus Temnodiscus mould whereas the specimen from Killara is on such inade- quate material is unwarranted. only an external mould. In view of this, the Furthermore, there is no evidence specimen from Loyola is accepted as the on the holotype of a holotype. sculpture of concentric rugae as claimed by Chapman. Until Material: Holotype, paratype and 12 other more specimens can provide specimens. further information, the specimen is left ten- tatively in this genus. Talent (1963) described Discussion: Comparison between this species two species of Temnodiscus from the similarly and the type species is limited by the mode of aged mudstones of the Kilgower Member in preservation of the former. The larger T. curvi- the Tabberabbera area of eastern Victoria. lineatus appears to have a deeper sinus and Family more regular growth lines than T. centrifugalis. SINUITIDAE Dall (in Zittel- The growth lines of T. centrifugalis appear to Eastman, 1913) be more foliaceous than those of the type Subfamily TREMANOTINAE Peel, 1 972 species. Otherwise, little comparison can be Genus Tremanotus Hall, 1865 made between the two species. (=Boiotremus Horny, 1962) T. centrifugalis differs from Tropidodiscus Type Species: Tremanotus alpheus Hall, 1865; sp. A. described by Talent (1963) from the Kil- Middle Silurian; Bridgeport, Illinois, U.S.A. gower Member, Tabberabbera, in the coarser, Tremanotus cyclocostatus Talent and Philip, more widely spaced nature of its collabral lines. 1956

(Plate 7, figures Genus Temnodiscus Koken, 1896 9, 13) 1916 Tremanotus pritchardi Cresswell; Chapman Type Species: Temnodiscus lamellifer (Lind- p. 79 (in part). strom), 1884; Middle Silurian; Visby, Gotland, 1956 Tremanotus cyclocostatus Talent and Philip pi. Sweden. p. 61, 6, figs. 11 & 15, pi. 7, figs. 16-17,' text fig. 4. GASTROPODS FROM WALHALLA SYNCLINORRJM 235

Diagnosis: Small form of genus with fine growth growth rugae and those present are irregularly lines and sculptural elements which can be developed. The finer spiral sculpture is more quite sinuous; few foliaceous growth rugae, numerous and irregular, often becoming quite irregularly developed. sinuous. Description: Medium, widely umbilicate, plani- 7\ cyclocostatus differs in a number of ways spiral form with a widely expanded aperture from T. pritchardi Cresswell, the only other in the final growth stage; whorl profile gently species described from Victoria (Tassell, arched dorsally, more strongly curved on the 1976). It is considerably smaller in size and sides when turning into the wide, deep, umbilici; has much finer growth lines and sculptural concave on the inner or columellar surface; elements. The spiral sculpture of T. cycloco- aperture in final growth stage sub-oval, greatly status is not as frequent and becomes quite expanded; neither a sinus nor tremata de- sinuous in places. The growth rugae are less veloped on the dorsal surface of the expanded frequently developed and those present are not region; the outer lip before the final growth as prominent as in T. pritchardi. During the stage strongly deflected posteriorly from the growth stages prior to the development of the columellar lip and culminates in a small slit flared aperture the outer lip of T. cyclocostatus situated medially on the dorsal crest of the is deflected more strongly posteriorly. Whereas outer surface; along the selenizone formed by the inner lip of T. pritchardi is straight, that of the slit numerous evenly spaced, sub-rectan- T. cyclocostatus is distinctly convex inwards. gular tremata are developed; the number of Chapman (1916), when discussing T. prit- open tremata unknown; between tremata the chardi from the Lilydale Limestone, noted that growth lines directed posteriorly towards the a specimen from the Thomson River had larger earlier tremata; prominent foliaceous rugae are tremata and a spiral sculpture that was more rarely developed; growth lines typically very sinuous. However, he considered it to be fine and closely spaced; sculpture composed of T. pritchardi. Re-examination of this specimen at least two orders of fine spiral elements; P913 reveals that it is quite clearly distinguish- sculpture irregularly spaced and frequently able from T. pritchardi and identical with quite sinuous; growth lines and sculpture form T. cyclocostatus. a reticulate pattern over whorl surface; sutures Family PLATYCERATIDAE Hall, 1859

deep. Genus Platyceras Conrad, 1 840 Dimensions: Subgenus Platyceras (Platyostoma) Conrad, L Wt Lap Wap Wit Wh 1842 M.U.G.D.2279 24* 12* — — 115 5 Type Species: Platyostoma ventricosum Con- M.U.G.D. 2167 19* — — — 11* — rad, 1842; Lower Devonian; near Saugerties, P913 47* — — — 17* 5 + New York, U.S.A. Location of Types: Melbourne University Discussion: Talent and Philip (1956, p. 59) Geology Department. Holotype, M.U.G.D. erected a new genus Ostlerina, distinguished 2279. Paratype, M.U.G.D. 2167. Hypotype, by being naticiform, narrowly umbilicate, with- M.U.G.D. 5031. out a sinus, with sculpture composed only of Type Locality: Toongabbie Limestone, lower growth lines and a simple nucleus. The type quarry, Marble Creek. species and only member of the genus was Material: Holotype and counterpart, one para- Ostlerina delicata Talent and Philip from both type, one hypotype and one other specimen. the quarries at Marble Creek. Subsequently Discussion: Comparison between this species Knight et ah (I960, p. 1240) synonymized this and the type species is limited by the nature genus with the subgenus P. (Platyostoma). The of preservation of the American species. How- assignment of the form from Marble Creek to ever, T. cyclocostatus is considerably smaller Platyostoma required the expansion of the sub- and has very much finer growth lines and generic concept to include minutely umbilicate sculptural elements. It has fewer foliaceous forms. 8

236 C. B. TASSELL

Platyceras (Platyostoma) incisum Chapman, most importantly in possessing a minute um- 1916 bilicus. It is also more explanate, has a lower

(Plate 7, figures 6, 14) spire, more rapidly expanded whorls and a very much larger aperture. The type species has an 1916 Diaphorostoma incisum Chapman, p. 99, pi. 5, fig. 46, pi. 6, fig. 59. obviously developed parietal inductura, a struc- 1956 Ostlerina delicata Talent and Philip, p. 59, ture wanting on P. (P.) incisum. pi. 6, figs. 1-4, text figs. 2-3. Diagnosis: Medium, explanate, minutely urn- Platyceras (Platyostoma) triangulare Talent bilicate form of the subgenus. and Philip, 1956 Description: Medium, explanate, naticiform, (Plate 7, figure 4) minutely umbilicate gastropod with several 1956 Platyostoma triangularis Talent and Philip, whorls; last whorl greatly expanded; spire p. 64, pi. 4, figs. 5-6. short, low; whorl profile moderately to gently Diagnosis: Small, naticiform gastropod with arched with a tendency to become flatter on the moderately irregular aperture and whorl profile last whorl; sutures adpressed; columellar lip which becomes angular with growth. long, thin and arcuate; no apparent parietal Description: Small, naticiform gastropod with inductura; outer lip thin, prosocyrt and slightly rapidly expanding whorls; large last whorl; low irregular; subcircular aperture large and very spire; whorl profile changes with growth, ini- shallow; growth lines irregular, becoming tially well rounded from the upper suture to coarser with age; no other sculpture present. the base with the periphery at mid-whorl; with growth whorl profile becomes more angular, Dimensions: gently rounded to nearly flat from upper suture Ht Wt Wl to angular P1083 — — 3 shoulder then nearly flat outer whorl M.U.G.D. 2164 15 5 24 8 3 surface to sub-angular basal periphery; base M.U.G.D. 2165 13- 22 6 3 nearly flat; umbilicus lacking; sutures change M.U.G.D. 2178 3 from canaliculate to impressed with growth; Location Types: of outer lip moderately thick, from the upper (i) D. incisum. National Museum of Victoria. suture it passes backwards to the shoulder, on Holotype, P1083. Previously 91F, Geological the outer whorl surface it is gently opistocyrt, Survey of Victoria Collection, forming a shallow wide sinus, from the basal (ii) O. delicata. Mebourne University Geology periphery it passes backwards across the base; Department. Holotype, M.U.G.D. 2164. Para- inner lip not known; aperture large, irregular; types, M.U.G.D. 2165 and 2178. sculpture of growth lines only. Type Locality: (i) D. incisum, Toongabbie Limestone, north- Dimensions: ern outcrop (or lower quarry), Marble Creek. Ht Wt Wh M.U.G.D.2175 7 6 11 5 1 (ii) O. delicata, Toongabbie Limestone, upper quarry, Marble Creek. Location of Types: Melbourne University Geo- logy Department. Holotype, Material: Holotype, 3 hypotypes and 13 other M.U.G.D. 2175. specimens. Type Locality: Toongabbie Limestone, lower quarry, Marble Creek. Discussion: The type locality for D. incisum is the northern outcrop of limestone, the site Material: Holotype. of the lower quarry of Talent and Philip (1956, Discussion: P. (P.) triangulare differs substan- text fig. 1). O. delicata is moderately common tially from P. (P.) incisum, the other species at this site, more so than at the upper quarry of the subgenus occurring at Marble Creek. where it is 'relatively rare' (Talent and Philip, Besides being much smaller than P. (P.) in- 1956). Comparison of all the material from cisum, it is characterized by a whorl profile both quarries indicates that O. delicata is a which becomes progressively more angular. It junior synonym of P. (P.) incisum. lacks an umbilicus and is more naticiform in P. (P.) incisum differs from the type species shape than the explanate P. (P.) incisum. The GASTROPODS FROM WALHALLA SYNCLINORIUM 237 latter' s growth lines are also considerably finer. decorum is much more sinuous and irregular Comparison of P. (P.) triangulare with the than that of P. (P.) vetustum. type species is limited by the lack of material The distinctive sinuous, almost crenulated from Marble Creek. It is smaller and more aperture of P. (P.) decorum is also a feature irregular. The whorl profile becomes progres- of the species of the subgenus Platyceras sively more angular with growth and the outer (Orthonychia) occurring at Marble Creek. lip is more irregular. These are all substantially larger than P. (P.)

Subgenus Platyceras (Platyceras) Conrad, 1840 decorum and do not possess its initial coiling. Type Species: Pileopsis vetusta J. de C. Sower- However, the great variability of this genus by, 1829; Lower Carboniferous; Queens and in cases only arbitrary distinctions between County, Ireland. subgenera means that P. (P.) decorum and P. (O.) marblecreekense may in fact be the Platyceras (Platyceras) decorum Talent and same species. Philip, 1956

1956 Platyceras decorum Talent and Philip, p. 64, Platyceras (Platyceras) minutum Chapman, pl. 7, fig. 21. 1916 Diagnosis: Small horn-shaped form of sub- (Plate 7, figure 8) genus with a sinuous to near crenulated small 1916 Platyceras minutum Chapman, pl. sub-circular aperture. p. 97, 5, fig. 41, pl. 6, figs. 57-58. Description: Small, irregular coiled, horn- Diagnosis: Small, regularly coiled, horn-shaped shaped gastropod with about two whorls; form with regular growth lines. nucleus initial coiled discoidally and whorl and Description: Small, horn-shaped gastropod of in contact; last whorl rapidly expanding and dis- 2-3 whorls; shell rapidly expanding; body junct; whorl profile sub-rounded with sub- whorl disjunct; whorl section sub-ovoid; from angular ridges to aperture, running from apex sutures whorl profile gently rounded to nearly variably developed; whorl section generally sub- flat, becoming well-rounded at the mid-whorl circular; aperture sinuous, irregular vari- and periphery; aperture ovoidal; outer lip from able; sculpture composed only of growth fines, both sutures strongly prosocyrt to the mid- concave toward the aperture on the ridges and whorl periphery; a broad open sinus formed the ridges. convex toward the aperture between at the mid-whorl; inner lip strongly curved; Dimensions: both lips thin; sculpture composed of pro- minent strong costae developed reasonably Ht Wt Wh M.U.G.D. 2173a 4-3 7-6 2 regularly; numerous finer growth lines between M.U.G.D. 2174 3-5 7-2 the costae.

Location of Types: Melbourne University Geo- Dimensions: logy Department. Holotype, M.U.G.D. 2173a Ht Wt Wh and b. Paratype, M.U.G.D. 2174. P12853 4-8 3 P41713 5-3 3 Type Locality: Toongabbie Limestone, lower P41714 5-2 3 quarry, Marble Creek. P41716 2-2 4-5 2

Material: Holotype and paratype. Location of Types: National Museum of Vic- smaller than Discussion: Besides being much toria. Holotype, P12853. Paratype, P12854. the type species, P. (P.) decorum does not Hypotype, P41713, A. W. Cresswell Collection. possess the typical capuliform shape because Type Locality: Deep Creek. of its slower whorl expansion rate. Accordingly, Material: Holotype, hypotype and three other the aperture of P. (P.) decorum is much specimens. smaller than that of the type species. The Marble Creek form also possesses distinct Discussion: The small number of specimens longitudinal ridges which are completely absent limits the comparisons that can be made on the type species. The aperture of P. (P.) between this species and P. (P.) vetustum. 238 C. B. TASSELL

P. (P.) minutum is smaller and is coiled more lips of variable thickness; sculpture lacking regularly than the capuliform type species. The except for exceedingly fine irregular foliaceous growth lines of P. (P.) vetustum are much growth lines and irregular rugae. more irregular than those of P. (P.) minutum. P. (P.) minutum differs considerably from Dimensions: P. (P.) decorum occurring at Marble Creek. Ht Wt Wh It is very much smaller and lacks the distinc- P12855 24* 32* 1+ P40344 37* 37* tive ridges of the latter form. Nor does it 1 + possess the distinctive irregular crenulated Location of Types: National Museum of Vic- aperture of P. (P.) decorum. It also expands toria. Holotype, P12855. more rapidly and more regularly than the Marble Creek form. Type Locality: Loyola Limestone, Loyola.

The species from Deep Creek is very similar Material: Holotype and two other specimens. to the initial growth stages of the Devonian Discussion: Chapman (1916) considered that P. (Platyceras) sp. from Canada, figured by the Loyola species was the same as the inter- Bowsher (1955, pi. 2, fig. 1) attached to the mediate, neritoid, depressed spire form of the crinoid Arthroacantha carpenteri Hinde. Both Silurian P. (P.) cornutum (Hisinger) from are of similar size and possess the same dis- Gotland, Sweden. tinctive simple sculpture and apertural shape. Originally figured by Hisinger (1828, pi. 6, However, with growth the Canadian form fig. 6) as Turbinites sp., this species is totally develops the irregular and variable growth different from the Loyola form. Similarly, the lines that are typical of the subgenus. figure of Pileopsis cornuta Hisinger (1837, Chapman (1916) considered that this species pi. 12, fig. 11) differs significantly from the resembled the initial growth stages of a variety Loyola form. Lindstrom (1884) redescribed of P. cornutum (Hisinger). As figured by Hisin Platyceras cornutum (Hisinger) and synony- ger (1828, pi. 6, fig. 6), (1837, pi. 12, fig. 11), mized with it a great range of forms of varying and Lindstrom (1884, pi. 2, figs. 29-51, pi. 3, ages from Europe. None of the forms which he figs. 6-9, 19-26) no specimen is comparable figured are comparable in terms of both general with the Deep Creek form. None of the speci- shape and sculpture with the Loyola species. mens figured by these authors possesses such Although the subgenera and species of this pronounced and regular growth lines as does genus exhibit considerable morphological vari- P. (P.) minutum or the Canadian form. Nor ation and are known to be intergrading, it is in general do the figured specimens cited by considered that the Loyola form is quite dis- Chapman lack spiral sculpture as does P. (P.) tinct from minutum. the Silurian P. cornutum occurring in Europe.

Platyceras (Platyceras) mansfieldense sp. nov. Platyceras (Platyceras) sp. A. (Plate 7, figure 11) Description: Medium, irregularly capuliform 1916 Platyceras cornutum (Hisinger) ; Chapman, gastropod with rapidly expanding whorls; large p. 97, pi. 5, fig. 42. last whorl; low spired; whorl profile changes Diagnosis: Large capuliform gastropod lacking with growth; from sutures whorl profile gently sculpture except for fine irregular foliaceous rounded at the mid-whorl periphery; with growth lines and irregular rugae. growth mid-whorl periphery weakens consider- Description: Medium to large, irregularly ably; whorl section changes from being sub- capuliform gastropod of one or two whorls, ovoidal to sub-circular with growth; aperture first whorl coiled discoidally and in contact; last sinuous, slightly irregular; sculpture consists whorl rapidly expanding and disjunct; whorl of fine slightly irregular foliaceous growth lines; profile sub-rounded; last whorl section sub- tendency for occasional growth rugae to ovate; aperture sinuous, irregular and variable; develop later. GASTROPODS FROM WALHALLA SYNCLINORIUM 239

intensions: Diagnosis: Small, umbilicate, subcylindrical Ht Wt Wh gastropod with few whorls, low to depressed msi 20-4 25-5 1+ spire, canaliculate sutures and narrow elongate Location of Types: National Museum of Vic- aperture. toria. Mentioned specimen, P44067. Description: Small, umbilicate, subcylindrical Type Locality: Toongabbie Limestone, Marble gastropod with few whorls, short to depressed Creek. spire and subcylindrical last whorl; sutures deep, canaliculate; whorl profile nearly flat Discussion: This species is readily distinguish- from upper suture to slightly obtuse shoulder, able from the other species of the subgenus outer whorl surface flat to sub-angular basal P. (Platyceras) found at any of the limestone margin, base rounded to nearly flat and near deposits discussed here. It is significantly perpendicular to outer whorl surface; aperture larger than either P. (P.) decorum or P. (P.) narrow, elongate; columellar lip long, thin; minutum although both have a comparable parietal lip short and of the same thickness as number of whorls. Both these smaller forms columellar lip; moderately thin outer lip passes appear to have growth sequences which differ slightly forwards from the upper suture to the from this species. The only other member of shoulder, on the outer surface it arches further the subgenus, P. ( P.) mansfieldense, is distin- forwards to mid-whorl so forming a distinct guishable by its considerably larger size, fewer deep sinus near the upper suture; below mid- whorls and different style of growth. whorl the lip passes backwards to just above Again the lack of specimens prevents a satis- the basal margin, from this point continues factory taxonomic assignment of the form or backwards much more strongly before turning comparison with P. (P.) vetustum. Certainly forwards midway across the base and con- the type species has a much more regular tinuing into the umbilicus; the second lower of expansion pattern growth, more rapid whorl sinus so formed is smaller but proportionally and more explanate aperture than this species deeper than the upper sinus; growth lines of from Marble Creek. varying size are well developed; sculpture Subgenus Platyceras (Visitator) Perner, 1911 possibly variably present, composed of very widely spaced spiral ridges on the outer whorl Type Species: Visitator extraneus Perner, 1911; surface. Silurian; Dvorce, Bohemia.

Discussion: The genus Cowwarrella was erected Dimensions: Ht by Talent and Philip (1956) and distinguished Wt Hap Wap Wh M.U.G.D.2169 12-9 10-8 — — 3+ by having a near rectangular whorl section, M.U.G.D. 2280 10 6 92 101 2 9 3 simple nucleus, absence of sculpture except M.U.G.D. 2281 — 6-4 — 1-9 3 growth lines, and an outer lip with an anteriorly Location of Types: Melbourne University Geo- directed tongue-like projection. Cowwarrella logy Department. Holotype, M.U.G.D. 2169. cylindrica Talent and Philip, the type species Paratypes, M.U.G.D. 2280-2281. from the and only member of the genus, was Type Locality: Toongabbie Limestone, lower Toongabbie Limestone, lower quarry, Marble quarry, Marble Creek. Creek. Distribution: Toongabbie Limestone and Deep Knight et al (1960, p. 1240) subsequently Creek Limestone. synonymized this genus with the subgenus Material: Holotype, 2 paratypes, and 4 other {Visitator). P. specimens.

Platyceras (Visitator) cylindricum (Talent Discussion: P. (F.) cylindricum differs signi- and Philip), 1956 ficantly from the type species. The form from Marble Creek is small and has a distinctive (Plate 7, figure 2) sub-cylindrical shape, whereas the type species 1956 Cowwarrella cylindrica Talent and Philip, is large and naticiform. Accordingly, the aper- p. 61, pi. 4, figs. 12-14. .

240 C. B. TASSELL

ture of P. (F.) cylindricum is narrow and (ii) Platyceras trirotundolobatum. Holotype, elongate while that of P. (F.) extraneum is M.U.G.D. 2168. sub-ovoidal. Knight (1941) considered the (iii) Orthonychia pentalvea. Holotype, M.U. type species to be 'seemingly anomphalous'. G.D.2170. P- (V.) cylindricum has an umbilicus. The Type Locality; Toongabbie Limestone, lower presence of this species at Deep Creek has not quarry, Marble Creek. been previously reported. Material: Holotype and 2 hypotypes. Subgenus Platyceras (Orthonychia) Hall, 1843 Discussion: As the holotype of P. trirotundo- Type Species; Platyceras (Orthonychia) sub- lobatum lacks the apical region of its shell, a rectum Hall, 1859; Devonian; near Williams- critical feature in the present classification of ville, Erie County, New York, U.S.A. subgenera of the genus Platyceras, the former name has not been selected as the senior Platyceras (Orthonychia) marblecreekense synonym. The holotype of O. marblecreekensis, Talent and Philip, 1956 which name has page priority over O. pentalvea, is complete, and the (Plate 7, figures 10, 12) former is accepted as the name for this taxon. 1956 Orthonychia marblecreekensis Talent and Philip, p. 65, pi. 7, fig. 22. The three species of the two subgenera 1 956 Platyceras trirotutuiolobatitm Talent and synonymized here are all uncommon, being Philip, p. 64, pi. 7, figs. 26-27. 1956 Orthonychia represented by only one specimen each. All pentalvea Talent and Philip, p. 65 pl. 7, figs. 28-29. come from the same locality. The known mode of life of members of these subgenera and the Diagnosis; Medium, variable horn-shaped form influence such a life has upon individual shell with up to 5 variably developed longitudinal morphology does not warrant the erection of ridges running from the apex to aperture. three separate taxa for three individuals from Description; Medium, horn-shaped, uncoiled the same locality. gastropod with up to 5 variable longitudinal The assignment of one form to the sub- ridges running from apex to aperture; shape genus Platyceras is unjustified in view of its irregular; initial region of the shell curved close similarity to the species of Orthonychia inwards; shell rapidly expanding; whorl sec- from the same locality and the absence of the tion irregularly polygonal to sub-ovoidal; apical region of the shell, the critical region in apertural margin irregular with a tendency to distinguishing between these two subgenera. have a crenulated appearance; lips thin; sculp- As preserved there is no suggestion that the ture absent except for longitudinal ridges and apical region of this shell was coiled. growth lines; growth lines variable, ranging All the specimens in this collection are con- from moderately regular fine lines which are sidered to belong to a single species. This convex towards the aperture between the longi- species is characterized by its medium size, tudinal ridges and concave towards the aperture uncoiled horn shape and the presence of about on the ridges, to coarse growth rugae which 5 variably developed longitudinal ridges. Other- although irregular are not sigmoidal or crenu- wise there is considerable variation, particu- lated. larly in the strength of the longitudinal ridges Dimensions; and the nature of the sculpture. These dif- Ht Wt Hap Wap Wh ferences are distinguished by the establishment M.U.G.D.2171 14-2 22 1 16 9 1 of 3 variants within the species, M.U.G.D. 2168 20 1 290* — 1 (i) Variant 1 (as represented M.U.G.D.2170 18 5 30-7 18 5 17-7 1 by the holo-

type, M.U.G;D. 2 1 7 1 ) Location of Types; Melbourne University Geo- This variant possesses the weakest logy Department. develop- ment of the longitudinal ridges. In some (i) Orthonychia marblecreekensis. Holotype, instances these ridges are not continuous from M.U.G.D.2171. the apex to the aperture. The ridges tend to be GASTROPODS FROM WALHALLA SYNCLINORIUM 241

more strongly developed in the apertural nature, minimal coiling and its great similarity region. The sculpture is exceedingly variable. with P. (O.) marhlecreekense. This latter

Initially fine crenulated growth lines are pre- uncoiled species is characterized by the pre- sent. This type of growth line is replaced sence of variably developed longitudinal ridges rapidly by coarse growth rugae which are and crenulated margin. Knight et al. (1960) roughly straight rather than crenulated. considered that the apertural irregularities of (ii) Variant 2 (as represented by hypotype the genus Platyceras were primarily a reflection M.U.G.D.2170). of the host crinoid's characters rather than an This more elongate variant is distinguished inherent characteristic of the gastropod. Thus by a decidedly more curved but totally disjunct the apparent absence of a crenulate margin in apical region. It also possesses fine, moderately P. (Orthonychia) sp. A. is not considered to uniform, growth lines which are typically be a significant taxonomic distinction between crenulated. The longitudinal ribs are continuous it and P. (O.) marhlecreekense. At present from the apical region to the aperture. these two species are differentiated on the basis of their coiling, general shape and the degree (iii) Variant 3 (as represented by hypotype M.U.G.D.2168). of development of the longitudinal ridges. However, further specimens may indicate that This variant is distinguished by the height of P. (O.) sp. A. is in fact another variant of the longitudinal ribs, which extend from the P. (O.) marhlecreekense. apical region to the aperture. The growth lines P. (Orthonychia) sp. A. is similar to P. (P.) are typically crenulated. mansfieldense in general appearance and the Platycera (Orthonychia) sp. A. nature of the growth lines. It differs in being much smaller, disjunct and having fewer (Plate 7, figure 7) whorls. Description: Medium, irregularly capuliform Subgenus Platyceras (Praenatica) Pemer, 1903 gastropod with one and a half whorls; disjunct Type Species: Strophostylus gregarius provea whorls expand rapidly; whorl profile probably Perner, 1903; Lower Devonian; Lockov, sub-rounded; last whorl section sub-circular; Bohemia. sculpture where preserved composed of moder- ately irregular growth lines; aperture slightly Platyceras ? (Praenatica) sp. A. irregular. Description: Large explanate naticiform to Dimensions: auriform gastropod; body whorl greatly ex- Ht Wt Wh panded; spire very low; sutures shallow; whorl 0* P1082 14 5 24 1 + profile changes with growth, becoming pro- gently rounded; whorl peri- Location of Types: National Museum of Vic- gressively more initially strongly toria. Figured specimen, P1082 ex G.S.V. phery in lower half of whorl, Collection, 91 F. rounded, becomes less pronounced and more gently rounded with growth; inner lip and Type Locality: Toongabbie Limestone, Marble umbilical region unknown; aperture large; Creek. outer lip moderately thin and irregular; from Material: Figured specimen on which the the upper suture the outer lip strongly pro- external sculpture is poorly preserved. socyrt; sculpture composed only of foliaceous provides an example Discussion: This specimen growth lines; coarse growth lines near apex. arbitrary distinction between the of the often Location of Types: National Museum of Vic- (Platyceras) and P. (Orthony- subgenera P. toria. Mentioned specimen, P40348. Rev. R. completely chia). Although having H coils it is Thomas Collection. disjunct. The availability of more specimens Type Locality: Loyola Limestone, Loyola. may enable its taxonomic status to be deter- Material: One crushed specimen. mined satisfactorily. At present it is placed in the subgenus Orthonychia because of its disjunct Discussion: The lack of material limits com- 242 C. B. TASSELL

parison with the type species. Externally both served, lacking both its nucleus and sculpture. species are very similar, although the Loyola If the initial whorls were in contact, this speci- species is slightly larger and has one more men would possess a distinctly capuliform whorl. The absence of internal details precludes shape which would distinguish it from P. (P.) definite subgeneric placement. decorum from Marble Creek, the only species of approximately similar size. Platyceras subgen. et sp. indet. 1956 Orthonychia sp. Talent and Philip, p. 66. Family ORIOSTOMATIDAE Wenz, 1938 Description: Small explanate gastropod with Genus Oriostoma Munier-Chalmas, 1876 gently rounded whorl profile; apical region Type Species: Oriostoma barrandei Munier- missing; sculpture composed of collabral lines Chalmas, 1876; Lower Devonian; Bois only preserved in the remaining 'apical' region; Roux quarry at Gahard, near outer lip thin; apertural margin apparently Rennes, France. regular. Oriostoma n. sp. Dimensions: (Plate 7, figure Ht Wt Hap Wap Wh 3) M.U.G.D.2182a 110 9-7* 110 8-7 1 Description: Small, low spired, discoidal gas- tropod with few whorls; Location of Types: Melbourne University Geo- whorls increasing in size rapidly; body logy Department. Mentioned specimen, M.U. whorl large; whorl profile G.D.2182. well rounded, from upper suture arched up- wards to rounded shoulder, then arched gently Type Locality: Toongabbie Limestone, upper to the round keel which surrounds the moder- quarry, Marble Creek. ately wide umbilicus, then curved more tightly Material: One specimen. into the umbilicus; periphery at or below mid- Discussion: Absence of the apical region pre- whorl; inner and outer lip thin; outer lip weakly cludes subgeneric determination. Although prosocline, retrousse at each of the major broken it is apparent that the apical region spiral sculptural elements; sculpture consists of narrows rapidly and curves, suggesting that two orders of numerous strong spiral elements; the shell may have been coiled. The regularity collabral growth lines range from moderately of the few growth lines and the segment of the fine to foliaceous and are retrousse at the aperture preserved distinguishes it from all intersection with each of the major spiral members of the subgenus P. {Orthonychia) elements. from Marble Creek. Dimensions:

? Platyceras subgen. et sp. indet. Ht Wt Wh P40319 5-4 3 1956 Platyceras sp. Talent and Philip, p. 65. P41727 11 6 Description: Small irregularly capuliform Location of Types: National Museum of Vic- platyceratid gastropod; rapidly expanding last toria. Figured specimen P41728, A. whorl. W. Cress- well Collection.

Dimensions: Locality: P403 19, Middle Crossing, Deep Ht Wt Hap Wap Wh Creek. P41727 and P41728, Deep Creek. M.U.G.D.2181 7-7 10-4 7-7 — 1 Material: Figured specimen and two other Location of Types: Melbourne University Geo- specimens. logy Department. Mentioned specimen, M.U. Discussion: This G.D.2181. species differs from 0. bar- randei principally in possessing many more Type Locality: Toongabbie Limestone, upper elements of spiral sculpture which are also more quarry, Marble Creek. strongly developed. In this respect alone it Material: One specimen. resembles the sculpture of Beraunia bifrons Discussion: single The specimen is poorly pre- (Perner). However, it is considerably smaller GASTROPODS FROM WALHALLA SYNCLINORIUM 243 than this species which is not a large member Dimensions: of the genus Beraunia. Because the spiral ele- Ht Wt Wh ments are more closely spaced in the form M.U.G.D.2172 25-8 8-6 8+ M.U.G.D. 2177 12-8 48 5 from Deep Creek, the posterior deflection of P38510 29* 100 9 the collabral growth lines at their intersection Location Types: Melbourne University Geo- with the spiral elements is markedly less than of logy that occurring in the type species. Department. Figured specimen, M.U.G.D. 2172. The Deep Creek form also differs from the type species in being smaller and having a more Type Locality: Toongabbie Limestone, upper rounded whorl profile. O. rotundimuratus quarry, Marble Creek. Tassell from the Lilydale Limestone is very Material: Figured specimen and 2 other speci- similar to the Deep Creek form. However, the mens. All material is poorly preserved. Lilydale species is slightly more turbinate and Discussion: Comparison of this material with has fewer, more widely spaced and less the two better known species M. brazieri strongly developed spiral sculptural elements. (Etheridge) from Lilydale and M. darwini Talent (1963) described and figured Orio- (de Koninck) from Taemas is difficult because stoma sp. from his locality 35 in the Kilgower of its very poor preservation. The specimens Member of the Tabberabbera Formation. The from Marble Creek are considerably smaller two specimens he found were poorly preserved than either of the other two species. and considerably smaller than the form from Chapman (1907) noted the presence of Deep Creek. Both species appear to have a Niso (Vetotuba) brazieri at Marble Creek. comparable number of spiral elements. How- This specimen (P38510) is very poorly pre- ever, Oriostoma sp. from the Kilgower Member served. The apertural region is not preserved lacks growth lines, so further comparison is nor is the columella visible. There is a sug- limited. gestion of a pseudoselenizone on the lower half Until more complete material is available of the last whorl. The disconcerting feature from Deep Creek I will not name this species. about this specimen is the rather more rapid expansion of whorl diameter compared to

Family MURCHISONIIDAE Koken, 1896 whorl height than is typical of either the other Genus Michelia Roemer, 1852 two specimens from Marble Creek or the other species. Assignment of this specimen to Type Species: Michelia cylindrica Roemer, two this genus is at best tentative. 1852; Devonian; Bockswiese, near Clausthal, Germany. Family PSEUDOPHORIDAE S.A. Miller, 1889 Michelia sp. Genus Scalaetrochus Etheridge, 1890 1907 Niso (Vetotuba) brazieri Chapman non Etheridge, pp. 73 and 79. Type Species: Trochus (Scalaetrochus) lind- 1913 Vetotuba brazieri Etheridge; Chapman, p. 227 stroemi Etheridge, 1890; Lower Devonian; (in part). Lilydale Limestone quarry, Lilydale, Victoria. 1916 Coelocaulus brazieri (Etheridge); Chapman, p, 86 (in part). Scalaetrochus Iindstroemi Etheridge, 1890 1956 Coelocaulus sp. Talent and Philip, p. 62, pi. 7, fig. 8. Description: Large trochiform gastropod with Description: Small to medium, narrowly umbi- mildly concave base; irregular sutures flush to licate, cyrtoconoid gastropod; numerous whorls slightly protruding; whorl profile gently convex; with profile gently convex between shallow periphery angular forming frill; peripheral impressed sutures; periphery about mid-whorl; region thickened by callus deposit; thickened pseudoselenizone outer lip moderately prosocline from upper apertural region unknown ; present on lower half of whorl; sculpture suture to the basal periphery, continues oblique- unknown. ly across the base; umbilical region unknown; 244 C. B. TASSELL

collabral growth lines, fine to slightly foliaceous References on the outer whorl surface; collabral lines on Bowsher, A. L., 1955. Origin and adaptation of the base fine. Platyceratid gastropods. Paleont. Contr. Univ. Kans. Mollusca. 1-11. Dimensions; Chapman, F., 1907. Newer Silurian fossils of eastern Ht Wt Victoria. Part I. Rec. geol. Surv. Vict. 2 (1): Wh 67-80. P40349 28* 34 6 , 1913. On the palaeontology of the Silu- rian of Victoria. Kept, Australas. Ass. Advmt. Location of Types: National Museum of Vic- Sci. 14: 207-235. toria. Mentioned specimen, P40349. G. Sweet , 1914. Newer Silurian fossils of eastern Collection. Victoria. Part III. Rec. geol. Surv. Vict. 3 (3): 301-316. Type Locality; Lilydale Limestone, Lilydale. , 1916. New or 1 ittle known Victorian fossils in the National Museum. Part XIX The Distribution; Lilydale Limestone and Loyola — Yeringian Gastropod fauna. Proc. R. Soc. Vict. Limestone. 29 (1): 75-103.

Cooper, B. J., Material: Mentioned specimen. 1973. Lower Devonian Conodonts from Loyola, Victoria. Proc. R. Soc. Vict. 86

) : 77-84. Discussion: Although only one specimen has ( 1 Couchman, T., 1877. Report of progress. been found at Loyola, it is sufficiently well Rep. Prog. geol. Surv. Vict. 4: 1-40. preserved for it to be assigned to this species. Hisinger, W. von, 1828. Anteckningar i Physik och Its presence there extends the known occur- Geognosi under resor uti Sverige och Norrige. 4 Stockholm. rence of this species. Chapman (1907, p. 73) , 1837. Lethaea Svecica seu Petrij acuta mentioned the presence of a fragment of Sveciae, iconihus et characteribus illustrata. Trochus (Scalaetrochus) sp. at Marble Creek; Holmiae. Knight, J. B., 1941. Paleozoic Gastropod Genotypes. as yet this specimen has not been relocated Spec. Pap. geol Soc. Am. 32: 510 p., 96 pi. and his identification confirmed. Knight, J. B., R. L. Batten and E. L. Yochelson, I960. Turbiniform gastropod gen. et sp. indet. Descriptions of Paleozoic Gastropoda In Moore, R. C, Ed. Treatise on Invertebrate Description: Small turbiniform gastropod of at Paleontology: 1. Mollusca (1). Univ. Kansas Press, 351 least 3 whorls; last whorl slightly expanded; p. Lane, G. N., 1973. Paleontology and paleoecology whorl profile gently arched between sutures, of the Crawfordsville fossil site (Upper Osagian: becoming more strongly arched onto the base; Indiana). Univ. Calif. Pubis geol. Sci. 99. Lindstrom, G., 1884. On the base arched; umbilicus probably present; Silurian Gastropoda and Pteropoda of Gotland. K. svenska Vetensk- sutures shallow, impressed; inner lip unknown; AkacL Hatidl. 19 (6). outerlip moderately thin, other details of outer Linsley, R. M., 1968. Gastropods of the Middle Devonian Anderdon lip unknown; aperture probably Limestone. Bull. Am ovoidal. Paleont. 54 (244). Murray, R. A. F., 1878. Geological Sketch-map, Dimensions: sheet No. 2, South-east Gippsland. Report. Rep. Prog, geol, Surv. Ht wt Wh Vict. 5: 44-70. Philip, G. M., 1974. Biostratigraphic Procedures and P41729 5-4* 5-2 3 + Correlations in the Tasman Geosynclinal Zone. In Denmead, A. K., Tweedale, G. W., Wilson, Location of Types: National Museum of Vic- A. F. (Eds.), The Tasman Geosvncline—a toria. Mentioned specimen, P41729. A. W. symposium. Geol. Soc. Aust. Qld Div. Cresswell Collection. Selwyn, R. C. and H. F. Ulrich, 1867. Notes on the Physical Geography, Geology and Miner- Type Locality: Deep Creek. alogy of Victoria 1-91. In Official Record of the Intercolonial Exhibition of A ustralasia, Mel- Material: Mentioned specimen. bourne. 1866-67. Strusz, D. L., 1972. Correlation of Discussion; The single specimen does not show the Lower Devonian rocks of Australasia. /. geol. Soc. Aust growth lines on the small fragments of the 18 (4): 427-455. Talent, J. A., outer shell present. Thus assignment to a genus 1956. Siluro-Devonian Brachiopods from Marble Creek, Thomson River. Proc is impossible. R However, its mode of coiling Soc. Vict. 68: 73-84. distinguishes it from all the other gastropods , 1963. The Devonian of the Mitchell and discussed. Wentworth Rivers. Mem. geol. Surv Vict 24* 1-118, 78 pi. — —— ,

GASTROPODS FROM WALHALLA SYNCLINORIUM 245

Talent, J. A. and G. M. Philip, 1956. Siluro- Figure 5 Tropidodiscus centrifugalis (Chapman) Devonian Mollusca from Marble Creek, Thom- P12844, holotype, XH approx. son River, Victoria. Proc. R. Soc. Vict. 68: Figure 6 Platyceras {Platyostoma) incisum Chap- 57-71. man, M.U.G.D. 2164, hypotype, XH. Tassell, C. B., 1976. A Revision of the Gastropod Apical view. fauna of Lilydale the Limestone (Early Devon- Figure 7 Platyceras (Orthonychia) sp. A., P1082, ian) Victoria. of Mem. natn. Mus. Vic. 37: figured specimen, X2 approx. 1-22. Figure 8 Platyceras (Platyceras) minutum Chap- Vandenberg, A. H. M., M. J. Garratt and man, P41713, hypotype, X3. D. Spencer-Jones, 1976. Silurian-Middle De- Figure 9 Tremanotus cyclocostatus Talent and vonian. In Douglas, J. G., and Ferguson, J. A. Philip, M.U.G.D. 5031, hypotype, X2 (Eds), Geology of Victoria. Spec. PubL geol. approx. Soc. Aust. 5. Figure 10 Platyceras (Orthonychia) marblecreek- Explanation of Plate ense Talent and Philip, M.U.G.D. 2171, holotype, X2 approx. PLATE 7 Figure 11 Platyceras (Platyceras) mansfieldense Figure 1 —? Temnodiscus pharetroides Chapman, sp. nov., PI 2855, holotype, XH approx. P12835, holotype, XI. Figure 12 Platyceras (Orthonychia) marblecreek- Figure 2 Platyceras (Visitator) cylindricum (Tal- ense Talent and Philip, M.U.G.D. 2170, ent and Philip), M.U.G.D. 2169, holo- hypotype, XH approx. type, X2. Apical view. Figure 13 Tremanotus cvclocostatus Talent and Figure 3 Oriostoma n. sp., P41728, figured speci- Philip, M.U.GJX 5031, hypotype, X2 men, XH. Apical view. approx. Figure 4 Platyceras {Platyostoma) triangulare Figure 14 Platyceras (Platyostoma) incisum Chap- Talent and Philip, M.U.G.D. 2175, man, P1083, holotype, XI. holotype, XH. Apical view. MEM. NAT. MUS. VICT. 38 PLATE 7

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