MORPHOLOGY AND AFFINITIES OF

K. R. SURANGE & SHALLA CHANDRA Birbal Sahni Institute of Palaeobotany, Lucknow-226007,

ABSTRACT

Reproductive organs of glossopterids, viz., Eretmonia, Glossotlleea, Kendos• trobus, Lidgettonia, Partlla, Russangea, M ooia, Rigbya, Denkania, Venustostrobus, Plumsteadiostrobus, Dietyopteridium and Jambadostrobus are briefly described. Their morphology and affinities are discussed. In the of the southern hemis• phere atleast two distinct orders of , viz., Pteridospermales and Glos• sopteridales were dominating the landscape.

genera bore sporangia terminally on ultimate GLOSSOPTERISAustralia were firstleavesrecordedfrom Indiaby Brong•and branches whereas the third bore niart in 1828. From 1845 to 1905, sporangia crowded on a cylindrical axis. a number of new species of Glossopteris were discovered from different continents of Eretmonia Du Toit Gondwanaland. From 1905 to 1950 there PI. 1. figs. 3,4; PI. 2, fig. 2; PI. 3, figs. 2,3 were only a few records, but from 1950 onwards Glossopteris again attracted the Fertile scale of Eretmonia (see attention of many palaeobotanists. At first, Chandra & Surange, 1977, text-fig. 1) are of Glos90pteris were regarded as but different shapes and sizes and five species later they turned out to be seed .. have been recognized on this basis. The In recent years our knowledge of the fertile bracts are ovate (E. ovoides Surange reproductive structures of glossopterids has & Chandra, 1974), spathulate with acute increased to such an extent that one can apex (E. hingridaensis Surange & Mahesh• get some idea as to what type of plants wari, 1970), triangular (E. emarginata they were. Chandra & Surange, 1977), diamond-shaped (E. utkalensis Surange & Maheshwari, 1970) HABIT and orbicular (E. karanpurensis Surange & Maheshwari, 1970). The sporangia are of Glos"opteris were plants is evi• Arberiella type and produced two winged dent from the abundance of isolated leaves spores. found in the Permian deposits of • The venation pattern in fertile scales of land. Many believe that Vertebraria were all species is almost the same. There is roots of the trees bearing Glossopteris leaves. no midrib but a few prominent bundles They were undoubtedly arborescent plants from the stalk enter the lamina and give out and many petrified woods described from secondary veins, which branch two to three Gondwanaland perhaps represent their stems. times, anastomose and form meshes as in Growth rings are common in the Glo"sopteris leaves. In all species of Eret• woods which point to prevailing seasonal monia net venation is clearly seen. growth periodicity. It is also certain that The fertile scales are stalked and after male and female reproductive organs were shedding the spores, the stalks get detached borne on different plants as in other groups from the bract lamina. One pedicel arises of gymnosperms. from the stalk which divides into two equal daU!~hterbranches. Each branch then suc• MALE REPRODUCTIVE ORGANS cessively divides by repeated dichotomy and the ultimate branches bear one sporangium Three types of sporangia bearing organs each at their tips and form a sporangial have been recognized under three different cluster. Thus two sporangial clusters are genera, viz., Eretmonia Du Toit, Glossotheca borne on one pedicel of one fertile bract. Surange & Maheshwari, 1970 and Kendostro• The sporangia are oval to elliptical with bus Surange & Chandra, 1974. The first two fine parallel lines on the sporangial surface 509 510 THE PALAEOBOTANIST

and are of Arberiella type. Detached Arbe• mizes immediately into two stout daughter riella type of sporangia are very common branches as in Eretmonia. Each branch in the Permian deposits of Gondwanaland. then further divides by repeated dichotomy Although, they look similar externally, it is so that possibly eight clusters of sporangia quite likely that each species contain dif• are formed on a single fertile scale. Sporan• ferent type of spores. In two cases, one gia are attached on the tip of the ultimate of the sporangium contained two winged branches and they are of striated Arberiella Faunipollenites type of spore and other type. The branching pattern of the pedicel contained Striatites type. is similar to that of Eretmonia. From the Most of the fertile scales are convex on size of the pedicels and their branching, one side and concave on the other. It is each cluster may contain not more than also thick in the middle and thin at the 32 sporangia. The sporangia are elliptical, margin. It must have acted as protective oval and striated. Although, they look alike cover to sporangial clusters which were externally, they differ in size and perhaps borne in its axil. Frequently detached in some other structural details and may sporangia are found preserved on the lamina have contained different types of spores. of the fertile scale. At maturity the sporan• At present very few carbonized sporangia gial clusters must have opened out enabling have been worked out (Chandra & Surange, the sporangia to shed their two winged 1977). The outer cells of the sporangium spores. wall are thick-walled, more long than broad It is true that Eretmonia has not been and twisted in various ways. These found attached to a Glossopteris . But thickened cells give a striated appearance there is hardly any doubt that Eretmonia to the sporangium so characteristic of type of male reproductive organ belongs to Arberiella. There is also a delicate layer of glossopterids. The fertile bracts of Eret• elongated cells. Sometimes spore mass is monia are in no way different from fertile seen covered with a tissue with extremely bracts of other reproductive organs assigned thin-walled cells. The sporangium, there• to (Surange & Chandra, fore, appears to be multilayered and the 1975). Moreover, Glossopteri51-like net vena• dehiscence is perhaps longitudinal. tion of the fertile bracts and their constant Isolated striated sporangia have been association with Glossopteris leaves further placed under the form genus Arberiella (Pant indicate their relationship with them. & Nautiyal, 1960). They are assigned to Eretmonia, Glossotheea and also to Pteruehus. Glossotheea Surange & Maheshwari Such sporangia have also been found attach• PI. 1, figs. 1, 2; PI. 3, fig. 1 ed to two rounded concave discs (attachment is different from Eretmom·a & Glossotheea). This genus has three species and is known There is, therefore, no doubt that the from India. It is on the same pattern as similar looking striated sporangia belonged Eretmonia but differs from it in possessing to diverse plants. Arberiella type contain more than one sporangia-bearing pedicels. two winged spores. A. afrieana contains All the three species are distinguished by Faunipollenites type of spores and A. their distinct fertile scales (see Chandra & vulgaris contains Lunatisporites type. Other Surange, 1977). Glossotheea utkalensis (Su• striated grains found in masses inside range & Maheshwari, 1970) has a spathulate the sporangia have not been identified with type of bract lamina with a long and stout genera of dispersed spores. stalk, G. orissiana (Surange & Chandra, 1974) has a rhomboidal bract and a short Kendostrobus Surange & Chandra stalk and G. 1·mmani51(Chandra & Surange, PI. 3, fig. 4- 1977) has a bract large in size, oblanceolate with a short broad stalk. In G. orissiana This male reproductive organ is organized and G. immanis four slender pedicels arise on a different pattern. It is a long, narrow, on the abaxial side of the stalk one below cylindrical, cone-like organ, bearing sporan• the other in a single row, some of them gia. The cylindrical sporangia-bearing axis look as if arising from the midrib region possesses very small, round protuberences of the bract lamina. In G. utkalensis three on which 4 to 5 sporangia are attached in pedicels are seen. Each pedicel dichoto- whorls. The whorls of sporangia in theiv SURANGE & CHANDRA - MORPHOLOGY AND AFFINITIES OF GLOSSOPTERIS 511

turn are carried on the axis in close spirals oblanceolate, spathulate-Ianceolate or ovate• and appear crowded on the cone surface. lanceolate, contracted at the base into a The sporangia are large in size, one whorl long stalk. The veins spread out from the occupyi~g almost the entire breadth of the base of the lamina, those in the middle cone aXIs. running straight upwards and the rest fork The sporangia are exannulate, oval to and form anastomes right upto the margin. elongate and the sporangial surface is Cupules or cupulate discs are attached in studded with oval to round depressions, two longitudinal rows by pedicels, arising giving it a spongy appearance. This type from the abaxial surface of the basal part of sporangium in detached condition is of the lamina. In Indian species, they described under a form genus Lithangium number eight, but Lacey et al. reported (Pant & Nautiyal, 1960). The spores are 4-14 cupules. There is, however, some stripped and monolete. Unmacerated spores differences in the interpretation of the show sculptine which is folded into curved bearing structure, due obviously to the ridges which are seen as longitudinal stripes imperfection of preservation. Lacey et al. in macerated spores. interpreted them as cupules, 4 to 14 in num• The mode of attachment of sporangial ber, open campanulate, sometimes appearing whorls in close spirals is something like that semicircular when compressed laterally or of seeds in which is found disc-like when compressed dorsiventrally. attached on a Glos~opteris leaf. However, Surange and Chandra (1974) interpreted neither a bract has been found in Kendo• them as circular, fluted discs, on the strobus nor it has been found attached to a under side of which small unwinged seeds Glos~opteris leaf. In dispersed condition. it are attached. The Indian and African is widely reported from a number of places specimens atleast represent two distinct in the Raniganj. It's affinities are un• species because the Indian species has certain, but because of its association with unwinged seeds and the African species has Glossopteris and in the absence of any other winged Samaropsis type of seeds. to which it can be referred to, we believe that it could be a male reproductive Partha Surange & Chandra organ of some glossopterid plant. PI. 2, fig. 4 This genus is a cupulate seed bearing FEMALE REPRODUCTIVE ORGANS reproductive organ and is represented by CUPULATE FRUCTIFICATIONS two species, viz., P. indica and P. spathulata (Surange & Chandra, 1973). The fertile A number of cupulate reproductive organs leaf is oval spathulate with broad apex, have been discovered in recent years from measuring 3-4 em in length. The petiole is the Permian deposits of India, South long and broad. There is no midrib but and . They are described under a few strong veins run in the middle right up to the apex. The secondary veins the genera Lidgettonia, Partlla, Denkania, arise from the outer veins, branch but Mooia, Rigbya and Russangea. anastomosing is rare, if not absent. Lidgettonia Thomas The cupules are borne in a single row, as against two rows in Lidgettonia, one PI. 2, fig. 1 below the other on short pedicels. Two Lidgettonia was first described by Thomas pedicels arise near the base of the lamina (1958) from Lidgetton, Natal and later by (there may be one or two more) almost Lacey et al. (1975) from Mooi River, both from the mid-veins. Four cupules are localities in . They were placed attached at the apex of each pedicels. under one species, Lidgettonia ajricana. Each cupule carries one seed. The seeds Another species, L. mucronata, is described are winged. from Orissa, India by Surange and Chandra Russangea Lacey, Dijk & Gordon-Gray (1974). Lidgettonia is a female fructification con• PI. 3, fig. 5 sisting of a fertile bract with stalked seed This cupulate fructification is very similar bearing cupules. The bract lamina is small, to Partha and is described by Lacey et al. 512 'fttE PALAEOBOTANIST

(1975) from South Affica. The fructification convex, each enveloping one seed at its consists of a petiolate fertile leaf bearing base. The seeds are 3-5 mm long and two scales, each with a single sessile seed. 2·5-3 mm wide, ovoid, flattened, but not The shape of the fertile leaf is that of a winged. narrow-ovate, petiolate, Glossopteris leaf. Rigbya arberioides is very similar to The venation is coarsely reticulate with Arbeiia winasica White. But Arberia is vertically elongated meshes. There is no much branched and not aggregated into a midrib but the centr:al bundles pursue a distinct head. Moreover, in Rigbya the close parallel course nearly to the apex. terminal scales are at least partially S1)r• Two seed bearing scales are attached at the rounding the scales and hence cupulate. base of the lamina on its adaxial side by short stalks. The scales are expanded Denkania Surange & Chandra distally, beyond the point of attachment PI. 3, fig. 6 of the seed, but Lacey et al. do not consider them cupulate. The two seeds are This genus is represented by a single oval and unwinged and are sessile on the species (Surange & Chandra, 1973). The scales. fertile leaf of this cupulate reproductive organ looks strikingly similar to a small Mooia Lacey, Dijk & Gordon-Gr:ay Glos>sopteris leaf. It is a narrow linear PI. 2, fig. 3 form, measuring about 5 cm in length with 1 cm long petiole. The mid-veins in the I t is yet another female fructification from lamina prominent, run parallel in the South Africa consisting of a petiolated middle, becoming narrow towards the apex fertile leaf bearing two to four stalked, but remaining impressively broad, occupying usually drooping, campanulate cupules. The almost the entire acute apex. The secondary lamina is spathulate or rhomboidal with veins arise from the outer straight veins, spoon-shaped depression surrounded by a repeatedly branch and form small, narrow nal7rOWmargin of thin texture. There is no meshes. midrib. The secondary veins dichotomize The cupules in Denkama are borne erect and reticulation is found in large laminae. on long pedicels on the abaxial side of the Two to four cupule bearing pedicels are petiole in a single row, one below the other. borne near the base of the lamina, attached A fertile leaf carries five to six cupules. singly or in pairs or possibly more than The pedicel is 1-1·5 cm in length and the two together in a single longitudinal row. cupule is about 1 em long and 6-7 cm The pedicel is upto 1 em long and carries a broad. The large and massive cupule is single cupule at its apex. The cupules are carried almost erect on the stalk and so the often reflexed, drooping, lobed and of stalk must have been provided with a variable size. The cupule lobes are from fair amount of strengthening tissue. The four to eight, longitudinally striated with a cupule is oval in shape, lobed and the fairly well-defined midline, acutely pointed, lobes may be three or more in number. fused basally to form the "cup" of the One cupule probably carries one large seed cupule, often appearing in spiral sequence and the seed is oval to elongate with a rather than a whorl. Seeds are borne broad wing-like integument. probably one per cupule, flattened and scarcely winged. They are not Samaropsis MULTI OVULATE FRUCTIFICATIONS type. Between 1952 to 1958, Plumstead in a Rig'bya arberioides Lacey, Dijk & series of papers described reproductive Gordon-Gray organs of Glossopteris under five generic Scutum, Lanceolatus, Hirsutum, Cis• PI. 2, fig. 5 names, telia and Plu'ma attached on different species This fructification has been described by of GZos'sopteris leaves. Plumstead's nomen• Lacey et al. as problematical. This is a clature procedure was at variance with the female fructification consisting of a stalk International Code of Botanical Nomen• bearing a terminal aggregation of seed• clature which created a confusion. How• beaping scales. The scale are long and eyer, in. 1958 she made it clear that Scutum, SURANGE & CHANDRA-MORPHOLOGY AND AFFINITIES OF GLOSSOPTERIS 513

Cistella, Hirsutum, etc. are not natural genera II. Cistella Type but they represent different types of fructi• Cistellaceae fication of glossopterids and should be (1) Plumsteadiostrobus ellipticus Chandra grouped as Scutum type, Cistella type, Hir• & Surange, 1977. sutum type, etc. We agree with Plumstead's Leaf - Glos:.opteris gondwanensis suggestion. The name Scutum, Cistella etc. Pant & Gupta, 1971. have become well-known by usage and no (2) Dictyopteridium feistmantelli Chandra purpose will be served by introducing new & SUl!ange, 1976. names for different types of glossopterid Leaf - Glossopteris tenuinervis Pant fructifications. It will only confound an already confused issue. Instead these groups & Gupta, 1971. could be raised to family level (Scuta• ceae, Cistellaceae, etc.) and the names III. Hirsutum Type Scutum, Cistella could be retained as form Hirsutaceae genera to include glossopterid fructifications (1) Jambadostrobus pretiosus Chandra & of which structural details are not known. Surange, 1977. Majority of fructifications are preserved as Leaf - Glossopteris contracta Pant impressions and there is, therefore, no chance & Gupta, 1971. of knowing any of their structural details. For such cases the form genera Scutum, Venu:.tostrobus indicus Chandra & Surange Cistella etc. would be very useful. When a fructification is known in sufficient Multiovulate types of glossopterid fructi• structural details, it could be described fication consisting of a seed bearing recep• under a new name as a separate organ tacle, is borne in the axil of a fertile bract. genus. Both are attached by their common pedicel It is now well-recognized that Glo!>:.opteris to the midrib of a vegetative leaf. The is a very loose form genus and its speciation stalk of the fructification is obviously adnate is very confusing. Add to it the imperfec• to the midrib of the leaf in the axil of which tion of preservation and the task of specific it is borne. The seed bearing receptacle is identification becomes formidable. One can thus placed between the fertile bract and the never be sure that one has correctly identi• vegetative leaf. The fertile bract is veined, fied a species of Glossopteris even after almost of the same shape and acts like a several years of experience in dealing with protecting spathe to the ovule bearing head. the material. Therefore, when a fructifica• The material of this fructification was tion is found attached on a leaf of Glossop• interesting. A complete leaf of Glossopteris teri!>species, the name of the fructification (a new species) was found covering under• should be given more importance and the neath it what looked like an orbicular name of the leaf could just become a outline of a fructification attached to it. synonym. The form genus Glos:.opteris The material was a coalified compression. should be retained to include only those We, therefore, took successive cellulose pulls leaves which are known morphologically but and studied them separately. This is what which cannot be assigned to a natural happened a thin coat of cellulose acetate genus. removed the leaf which was on top of Recently, different types of glossopterid the fructification. The fructification thus fructifications with structural details were exposed revealed small round seed-like bodies described: in a mass, badly compressed. When the second coat of cellulose acetate was applied, I. Scutum Type the mass of seed-like bodies were removed, Scutaceae exposing the veined fertile bract. The third (1) Venu:.tostrobtts diademu!> Chan dra & pull removed the carbonized crust of the Surange, 1977. bract. Below that there was shale matrix. Leaf - Glossopteris ghu!>illensis Pant There is no doubt that the fructification & Gupta, 1968. was attached to the vegetative leaf under (2) Venustostrobus indicus Chandra & which it was lying. The fructification was Surange, 1977. in the basal region where it shoutd be and Leaf - a new species of Glossopteris. th,e orbicl.llar outline was visible on both 514 THE PALAEOBOTANIST

sides of the midrib. Imprint of the seed pattern. The nonstomatiferous surface has mass made the leaf surface uneven. large, straight-walled cells and a few hair When the first pull was macerated, tough bases. The stomatiferous surface has much cuticles of leaf, both from the abaxial and shorter, moderately thickened cells, stomata the adaxial sides, were recovered. When the and highly thickened hair bases in large third pull was macerated, it yielded the numbers. It appears that one surface of the cuticles from the two sides of the fertile bract possessed stiff hairs. bract and were quite distinct from those The seed bearing receptacle is orbicular of the leaf recovered from the first pull. in shape and carries spirally arranged sessile The second pull after maceration yielded, seeds. The cuticle of the receptacle has besides a few pieces of leaf and bract, two types of cells. The cells around the seed pieces with integument and nucellar seed are small, papillate, squarish with tissue attached to them and quite a number firm, dark coloured, thickened cell walls. of distinct cuticular pieces which we ascribed The cells in between the seeds are large, to the seed bearing axis or the receptacle. thin-walled, non-papillate and contain The distinct cuticles of leaf and bract show stomata. Does the thickened layer below that they are separate organs. Furthermore, the seed help in shedding? The seed is the cuticles of the leaf to which fructification small, roundish with chalaza 1 end always is attached and those of other vegetative found torned. The integument cells are lea ves without fructification are identical, large, arranged end to end and straight• showing thereby that there is no difference walled. The cells at the micropylar end between the two. The reproductive organ are elongated, narrow, slightly thickened thus could be borne in the axil of any and show slightly sinuous cell walls. The vegetative leaf of a shoot. If there is an nucellar membrane is thin and show obscure axis on which the seeds are attached cell outlines. The seed is filled with thick (as proved by a distinct type of cuticle) opaque tissue and often contain two winged the entire reproductive organ cannot be pollen grains. dorsi ventral as supposed by Plumstead and some other authors. On the other Jambadostrobus pretiosus Chandra & Surange hand, the presence of a seed bearing axis PI. 4, fig. 2 or receptacle has been clearly demonstrated. Furthermore, if the seeds are arranged in It is a distinct type of multiovulate close spiral, it cannot be a dorsiventral organ in which more than one seed bearing organ. receptacles are attached on the midrib of a single leaf and the receptacles are naked Venustostrobus diademus Chandra & Surange in the sense that there is no protective PI. 4, fig. 3 fertile brae t. Jambadostrobus pretiosus is attached by a It is another Scutum type of fructification short stalk on the midrib of Glossopteris borne on a different type of leaf, Glosso• contracta Pant & Gupta, 1971. The leaf pteris ghusikensis. The multiovulate organ has been identified on both external as well is attached by a short stalk to the midrib as cuticular characters. The receptacle is of a small, petiolate, open mesh type of 2-3 cm in length and 1 cm in breadth. leaf. It is circular to orbicular in outline It is elliptical or lenticular in shape, carrying and has a wide border, divided transversely large naked seeds on seed cushions in close into rectangular areas. Strongly veined spirals. The apex of the receptacle is fertile bract fits closely on the seed bearing drawn out like a beak, appearing like a head or receptacle. crown. The margin is fairly broad, but The fructification bearing leaf is identical not as broad as Venustostrobus and is divided with Glossopteris ghusikensis described earlier by transverse markings left by the marginal by Pant and Gupta (1971) in external seeds. The cuticle of the receptacle has as well as cuticular characters. The protec• small isodiametric, moderately thickened tive bract has strong, prominent veins cells and the entire cuticle is covered which fan out from the pedicel, branch and with stripes of cuticular thickenings. The form narrow meshes. Two sides of the marginal cells are large and thin-walled. bract show two different types of cell The stomata are arranged in small circles ~U1iANGE & CHANDRA - MORPHOLOGY AND AFFINITIES OF GLOSSOPTERIS 515

where the cuticle is very thin or almost almost zig-zag. The winged pollen grains, absent. This is a characteristic feature of generally seen inside the pollen chamber, the receptacle cuticle. are Faunipollenites type. The seeds are large in size and are Platicardia bengalensis type described by Dictyopteridium feistmanteli Chandra Pant and Nautiya1 in dispersed condition. & Surange The outer cuticle of integument contain Pi. 1, fig. 1 imprints of tetra- to octahedral crystals, some of them possessing short tails. The There are two species of this genus, nucellar cells a.re thickened with deeply Dictyopteridium sporiferum Feistmante1, sinuous to zig-zag lateral walls. 1881 and D. feistmanteli Chandra & Surange, 1976 which is based on a compressed Plumsteadiostrobus ellipticus Chandra material. & Surange The fructification is attached by a short Pi. 4, fig. 4 stalk to the petiole, just at the base of the leaf of Glossopteris tenuinervis Pant & It is a Cistella type of fructification Gupta, 1971. borne on the leaf of Glossopteris gondwanensis The fertile organ consists of a seed bearing Pant & Gupta, 1971 attached by a ~hort receptacle borne in the axil of a stalked stalk to the midrib in the basal region. fertile bract which covers it like a protective It consists of a seed bearing receptacle spathe. The fertile scale is somewhat thick borne in the axil of a spathe-like protective and stalked. A few parallel veins run fertile bract and possessing a common stalk in the middle like a midrib. The secondary by which it is attached to the midrib veins branch and anastomose. The cuticle of the leaf. on one side of the bract has isodiametric The fertile bract is veined. There is no cells with firm cell walls and numerous midrib, but a few parallel veins run in the one-celled hairs or papillae. The other side middle and the secondary veins branch has thin-walled rectangular cells and no hair once or twice and form meshes. The bra.ct at all. The receptacle is lanceola te and yields one thick and one thin cuticle. The narrow and is covered with small round thin cuticle shows stomata. The receptacle seed-cushions. They are arranged in close cuticle has 1ense-shaped holes around which spirals, or some of them might appear the cells are arranged in radial rows. The as if arranged in arch. The receptacle cuticle is also dotted with what looks like cuticle is somewhat thick, covered with a secretory cells or hair bases. The lenticular network of stripes of cuticular thickenings. holes are the places where seeds are attached The cells are thin-walled and dotted with and through which vascular supply must thickened, one-celled hairs. The seeds are ha ve passed from the receptacle to the attached on seed cushions. The seed is . The seeds are arranged in close small, unwinged with pointed micropylar spiral. The seeds are Pterygospermum rani• end. The cells at the micropylar end have ganjense described by Pant and Nautiya1, wavy cell walls. The nucellar membrane is 1960 in dispersed condition. The outer thin without any cellular markings. covering of the seed expands into a wing. which is broad at the mycropy1ar end and DISCUSSION narrow at the cha1aza1 end. The" wing" which is an extension of the integument G10ssopterids are a class of seed plants is is continued on either side of the micropyle. no longer in doubt. The problem of determin• The cells of the outer integument contain ing affinities among glossopterids, and their crystalline imprints which are mostly hexa• position among different groups of gymnos• gonal or rectangular and very character• perms would be nearer solution if their istic of this seed. The nucellus is thickly reproductive structures are correctly inter• cutinized and shows an excavated pollen preted. Different interpretations are in chamber on top. Surface cells of the pollen vogue. P1umstead (1952) interpreted the chamber are elongated and have delicate reproductive structure as pedicellate, flatten• wavy walls. Other cells of the nucellus ed, dorsiventra1 cupu1e, the fertile half are thin, elongated and deeply sinuous or having a raised head, containing small oval 516 THE PALAEOBOTANIST

sacs and a flutted or striated wing. Later, 4. The seeds are arranged in close spiral she (1956) described the cupule as bisexual which is not possible if the fertile head was flower, the fertile half containing the seeds dorsiventral. Seeds still stuck together in and the other half bearing bract-like stami• spiral manner were found as such, or some• nate organs. Schopf (1976) agrees with times entangled with the receptacle cuticle Plumstead in regarding the reproductive on which they must have been borne. organ as flattened, dorsiventral, bilaterally 5. Striated "wing" is nothing but the symmetrical structure, having different fea• impressions left by seeds on the margin of tures on dorsiventral surfaces. He suggested the recepta.cle. The seeds are arranged a new term" fertiliger " for the reproductive one below the other as is seen in cases structure, which consists of a leafy bract where although some seeds were shed, (the vegetative leaf on which the fructifica• the others remained still sticking to the tion is attached), a partially adnate stalk receptacle. The width of the "wing" and a fertile head or capitulum. Surange depends upon the size of the seeds. The and Chandra's interpretation is more akin to bigger the seed, wider is the "wing". that of Edward's and Walton's in regarding The seed bearing head is thus a strobilus the fertile heads as cone-like or strobilar. without ovuliferous bracts. It can in no They regard the seed bearing central axis way be compared with a pteridospermous or receptacle essentially as cylindrical, oval cupule. Therefore, no new term such as or lenticular, bearing ovules in close spiral " fertiliger" is required to describe this all round the axis and borne in the axil simple multiovula te, strobilar type of Glossop• of a stalked, veined bract, which also acts teris reproductive structure. What Scopf like a protective spathe. The common (1976) calls as "fertile bract" is really an stalk of bract and seed bearing receptacle is ordinary vegetative leaf which is in no way attached to the midrib of an ordinary leaf different from other similarleaves, externally of Glossopteris to which it is partially as well as in cuticular structure. On the adnate. Thus the reproductive structure is other hand, the veined part adpressed borne in the axil of a leaf and the seed to the fertile receptacle is truely a fertile bearing receptacle occupies a position in bract and quite different in structure from between the fertile bract and the vegetative a vegetative leaf. leaf. The reasons for strobilar interpretation It is not yet fully appreciated that the are as follows: so-called glossopterids possessed two distinct 1. Compressions of the reproductive struc• types of reproductive structures., In one ture have shown that the veined bract group the ovules were attached 'to mega• and the seed bearing receptacle are two or modified megasporophylls separate organs and not a single plant organ and could come nearer to the pterido• with veined adaxial and fertile abaxial sperms. These could be dorsiventral struc• surface. The veined bract yielded two types tures. The other group possessed a strobilar of cuticles, obviously one from its adaxial type of reproductive structure as shown and the other from the abaxial surface. clearly now by compressed material. The The receptacle yielded a distiflct cuticle difficulty in understanding the glossopterid which is easily distinguishable from the fructifications arises when one tries to bract cuticles. Therefore, two separate plant interpret the strobilar type as cupulate or organs (and not one organ) are involved dorsiventral structure, drawing upon vague here. morphological terms, or even coining new 2. Detached fertile bracts and detached morphological terms. It only adds to the seedless receptacles are found preserved confusion. separately. Hence, they are two separate The cupulate types were co-existing with organs. The cuticles of detached bracts are the multiovulate strobilar types, although identical with the cuticles of bracts attached perhaps the cupulate types, like Arberia to fructification. were present in the Karharbari Stage. 3. In one compression it was possible The cupulate reproductive structures are to remove the vegetative leaf, seed mass, organized on a different pattern and come the receptacle and the bract by successive closer to the pteridosperms, particularly the cellulose pulls, showing thereby they are ones of the . all separate and distinct organs. Here some of the structures like the one SURANG~ & CHANDRA- MottpHoLOGY ANt'> AFFl l1'tES OF GLOSSOPTERIS 517

described as Ottoharia by Pant (1977) and Order - GLOSSOPTERIDALES the petrified ovulate fructification described recently by Gould and Delevoryas (1977) Family - (1) Cistellaceae where the seeds are borne on one side of a Dict)lojOteridium megasporophyll, may be dorsiventral organs Plumsteadiostrobus such as Lidgettonia (Surange & Chandra, Family - (2) Scutaceae 1974) and some other cupulate fructifica• Ottoharia tions described by us. The fertile bract or Venustostrobus megasporophyll in cupulate fructifications Family - (3) Hirsutaceae is a small, specialized appendage with ] ambadostrobus type of venation and is not comparable to the ordinary vegetative leaves ORIGIN of multiovulate strobilar types on which the reproductive structures are borne. How• The origin of the glossopterids is shrouded ever, the mode of attachment of cupulate in mystery and it will remain so far the types appears to be similar to the multi• lack of fossil record immediately preceding ovulate types, in the sense that the stalk the first appearance of GlossojOteris. Before of the cupules or cupulate disc is attached the Gondwana glaciation, the Lower Carboni• to the petiole or the midrib of the fertile ferous RhaeojOteris, flora was present in the bract in its ba:al region. Either the cupules southern hemisphere and immediately after are attached to the fertile bract individually the glaciation, or perhaps during the glacia• by their stalks or there is a stalked cupulate tion itself, GangamojOteris-GlossojOteris flora disc to which ovules are attached. In had already come into existence. This is a cupulate types there is thus no aggregation gap in the fossil record and therefore, any of naked ovules on a central axis as in phyletic model for glossopterid evolution the multiovulate reproductive structures of would remain at best a speculation. Glossopteridales. It must be pointed out Perhaps the strongest point against the here that cupulate types have not so far derivation of GlossojOteris from the eordai• been found attached to typical Glossopteris teans (Schopf, 1976) is the absence of true leaves. However, the net venation of the cordaites in the southern hemisphere. To fertile bract is like Gangamopteris and the attribute NoeggerathiojOsis to mode of attachment of the reproductive on the basis of similarity in vegetative structure is also like glossopterids. There is leaves is as good as attributing GlossojOteris also no leaf other than Glossopteris present to ferns on the basis of venation. The in the material to which multiovulate types ovulate fructification, Arberia, which is could be referred. attributed by some authors to Noeggera• Thus in glossopterids of the southern thiojOS'is, is built on the same pattern as hemisphere, there were atleast two distinct some of the later cupulate types of fructi• orders of gymnosperms, apart from Buriadia fications and could as well be put under the type of conifer-like plants, which were pteridosperms. If in Arberia the arrange• dominating the landscape. We would like ments are pinnate, then the ovules could be to put the cupulate types, presuming that considered as borne on modified frond. the ovules are borne on a modified frond, It is not definitely known what type of leaf the megasporophyll, under the pteridosperms ~ore Arberia. The other known reproduc• for the present and classify glossopterids as tive structure of the same age, Ottokaria is follows: attached definitely on the leaf of GlossojOteris Order - PTERIDOSPERMALES communis in the type specimen. We do not know what type of reproductive organs Family - (1) Parthaeeae GangamojOteris possessed. So Arberia could Partha as.wel! belong to Gangamopteris or Noeggera• Russangea thwjOsts, the two genera then existing, apart Family - (2) Lidgettoniaceae from Glosso:J:teris. All the three genera, Lidgetlonia Gangamopterts, Glossopteris and Noeggera• Family - (3) Denkaniaceae thiopsis were thus co-existing (and so were Denhania Arberlia & Ottokaria) and to derive one fv.looia from the other does not appear plausible. 518 THE PALAEOBOTANIST

It clearly shows that the two distinct types Looking at the reproductive structures in of reproductive structures, one cupulate various groups of fossil and living gymnos• type as represented by Arberia and the perms, it appears likely that the evolution strobilar multiovulate type as represented in seed plants diversified at least in three by Ottokaria were already present in the directions quite early in its history (Lower Lower Permian. The same two types, re'• ?), almost at its beginning. presenting two orders, diversified and multi• The three main lines suggested are (i) plied in the latter part of the Permian Pteridosperm - Cycad complex, (ii) Glos• (Raniganj Stage). The origin of two types sopterid complex, possibly giving rise to of reproductive structures therefore has Pentoxyleae and Cycadofilicales, and (iii) to be traced back to the Middle Carboni• Cordaitean - Conifer complex. Text-fig. ferous period, particularly in the early seed 1 illustrates a tentative working hypothesis plants, the fossil records of which are suggesting possible evolutionary lines in seed unfortunately missing in the Gondwanaland. plants.

(/) lLJ -oJ 4: ~ ex: lLJ a• (/) ~ (/) TRIASSIC ~ 8

PERMIAN

(/) lLJ \ -oJ \I I ~ I CARBONIFEROUS I I ~ , I ex: , I I ,0 \ \U I " , '---~------""-----..,' ,, ",__ PRIMITIVE SEED PLANTS

TEXT-I'IG. 1 SVRANGE & CHANDRA- MORpHOLOGY A D AFFINITIES OF GLOSSOPTERIS 519

Three distinct evolutionary complexes to Coniferales and possibly . The possibly arose from the primitive seed plants. glossopterid complex perhaps gave rise to One was pteridosperm copmlex, the second Rajmahalia type of plants and the southern was cordaitalean complex, and the third was hemisphere Pentoxyleae. The bennettitalean glossopterid complex. The first perhaps " flower" might have also arisen from the gave rise to groups like Lidgettoniales, Cory• multiovular type of reproductive structure stospermales and other groups of pterido• like that of the Glossopteridales. At least sperms. From this group perhaps arose the aggregation of ovules on a receptacle was Cycadales. The second comple" gave rise first achieved in Glossopteridales.

REFERENCES

BRONGNIART, A. (1828). Histoire des Vegetaux seeds and sporangia of Glossopteris Flora from fossiles ou recherches botaniques et geologiques Raniganj Coalfield, India. Palaeontographica, sur les vegetaux re1tfermes dans les diverses cou• 107B (1-3): 41-64. ches du globe. Paris. PLUMSTEAD,E. P. (1952). Description of two new CHANDRA, S. & SURANGE, K. R. (1976). Cuti• genera and six new species of fructifications cular studies of the reproductive organs of Glos• borne on Glossopteris leaves. Trans. geol. Soc. sopteris Part 1. Dictyopteridium feistmanteli S. Afy., 55: 281-328. sp. novo attached on Glossopteris tenuinervis. PLUMSTEAD,E. P. (1956). On Otlokaria, the fructi• Palaeontograpkica, 156B (4-6): 87-102. fication of Gangamopteris. Trans. geol. Soc. CHANDRA, S. & SURANGE, K. R. (1977). Cuti• S. Afr., 59: 211-236. cular studies of the reproductive organs of Glos• PLUMSTEAD,E. P. (1958). Further fructifications sopteris Part 2. Cistella type fructification Plums• of the Glossopteridae and a provisional classi• teadiostrobus ellipticus gen. et sp. nov., attached fication based on them. Trans. geol. Soc. S. on Glossopteris taenioides. Feistmantel. Palaeo• Afy., 61: 51-76. botanist, 23 (3): 16-174. SCHOPF, J. M. (1976). Morphologic interpretation CHANDRA, S. & SURANGE, K. R. (1977). Cuti• of fertile structures in Glossopterid gymnosperms. cular studies of the reproductive organs of Rev. Palaeobot. Palynol., 21: 25-64. Glossopteris. Part - 3. jambadostrobus and SURANGE, K. R. & MAHESHWARI,H. K. (1970). Venustostrobus borne on Glossopteris leaves. Some male and female fructifications of Glossop• Palaeontographica, 164B (4-6): 127-152. teridales from India. Palaeontographica, 129B: CHANDRA, S. & SURANGE, K. R. (1977). Cuti• 178-191. cular studies of the reproductive organs of SURANGE, K. R. & CHANDRA, S. (1973). Dic• Glossopteris Part-4. Venustostrobus indicus sp. tyopteyidium sporiferum Feistmantel female cone novo Palaeobotanist, 24 (3): 149-160. from the Gondwana of India. Palaeobotanist, CHANDRA, S. & SURANGE, K. R. (1977). Fertile 20 (I): 127-136. bracts and scales of Glossopteris fructifications SURANGE, K. R. & CHANDRA, S. (1973). Den• from the Lower Gondwana of India. Palaeo• Ilania indica gen. et sp. novo A Glossopteridean botanist, 24 (3): 195-201. fructification from the Lower Gondwana of CHANDRA, S. & SURANGE K. R. (1977). Some India. Palaeobotanist, 20 (2): 264-268. scalf.' leaves and sporangia from the Raniganj SURANGE, K. R. & CHANDRA, S. (1973). Part/w, Coalfield, India. Palaeobotanist, 24 (3): 245-253. a new type of female fructification from the FEISTMANTEL,O. (1880-81). The fossil flora of the Lower Gondwana of India. Palaeobotanist, 20 Gondwana System (Lower )-2. (3): 350-360. The flora of Damuda-Panchet divisions. Palae• SURANGE, K. R. & CHANDRA, S. (1974). Lid• ont. indica, ser. XII, 3 (2): 1-149. getlonia mucronata sp. novo a female fructifica• GOULD, R. E. & DELEYORYAS,T. (1977). The bio• tion from the Lower Gondwana of India. Palaeo• logy of Glossopteris. Evidence from petrified botanist, 21 (1): 121-126. seed-bearing and pollen-bearing organs. Alche• SURANGE, K. R. & CHANDRA, S. (1974). Fruc• ringa, 1: 387-399. tifications of Glossopteris from India. Palaeo• LACEY, W. S., DIJK, D. E. & GORDON-GRAY,K. D. botanist, 21 (1): 1-17. (1975). Fossil plants from the Upper Permian SURANGE, K. R. & CHANDRA, S. (1974). Fur• in the Mooi River district of Natal, South Africa. ther observations on Glossotheca Surange & Ann. Natal. Mus., 22 (2): 349-420. Maheshwari, a male fructification of Glossop• PANT, D. D. (1977). The plant of Glossopteris. J. teridales. Palaeobotanist, 21 (2): 248-254. Indian bot. Soc., 56 (1): 1-23. SURANGE, K. R. & CHANDRA, S. (1974). Some PANT, D. D. & GUPTA, K. L. (1968). Cuticular male fructifications of Glossopteridales. Palaeo• structure of some Indian Lower Gondwana botanist, 21 (2): 255-266. species of Glossopteris Brongniart. Part - I. SURANGE, K. R. & CHANDRA, S. (1975). Mor• Palaeontographica, 124B (1-3): 45-81. phology of the gymnospermous fructifications PANT, D. D. & GUPTA, K. L. (1971). Cuticular of the Glossopteris flora and their relationship. structure of some Indian Lower Gondwana Palaeontographica, 149B (5-6): 153-180. species of Glossopteris Brongniart Part - H. THOMAS, H. H. (1958). Lidgetlonia, a new type Palaeontographica, 132B (1-4): 130-152. of fertile Glossopteris. Bull. Br. Mus. (nat. PANT, D. D. & NAUTIYAL, D. D. (1960). Some Hist.) geol., 3 (5); 179-189. S20 THE PAtAEO'BOl'ANlST

EXPLANATION OF PLATES

PLATE 1 PLATE 3

1. Glossotheca immanis Chandra & Surange. X 2. 1. Glossotheca orissiana Surange & Chandra. X 2. 2. Glossotheca utkalensis Surange & Maheshwari. 2. Eretmonia ovoides Surange & Chandra. X 2. X 2. 3. Eretmonia utkalensis Surange & Maheshwari. 3. Eretmonia hingridaensis Surange & Mahesh• X 2. wari. X 2. 4. Kendostrobus cylindricus Surange & Chandra. 4. Eretmonia emarginata Chandra & Surange. X 2. x 2. 5. Russangea elegans Lacey et al. Pencil draw• 5. Rigbya arberioides Lacey et al. Pencil drawing ing made from specimens NM 1361a and NM1363a made from photographs of specimens r.. M 1644a of Lacey et al., 1975. X 2. and NM 1669 of Lacey et al., 1975. X 2. 6. Denkania indica Surange & Chandra. X 2.

PLATE 2 PLATE 4

1. Lidgetlonia mucronata Surange & Chandra. 1. Dictyopteridium jeistmantel-i Chandra & X 2. Surange. X 2. 2. Eretmonia karanpurensis Surange & Mahesh• 2. ] ambadostrobus pretiosus Chandra & Surange. wari. X 2. X 2. 3. Mooia lidgetlonioides Lacy et al. Pencil draw• 3. Venustostrobus diademus Chandra & Surange. ing made from photograph of specimen NM 1476b X 2. of Lacey et al., 1975. X 2. 4. Plumsteadiostrobus ellipticus Chandra & 4. Partha spatulata Surange & Chandra. X 2. Surange. X 2. SURANGE & CHANDRA - MORPHOLOGY AND AFFINITIES OF GLOSSOPTERIS 521

5

3

2

PLATE 1 tHE PALAE0l30TANtsT

3

4

FLATE ~ tJRANGE & CHANDRA - MORPHOLOGY A,~D AFFlr ITIES OF GLOSSOPTERIS S~1

5

2 ,

3 524 THE PALAEOBOTANIST

fLATE 4