III.—ON THE PLANT REMAINS FROM THE BRAZILIAN COAL BEDS, WITH REMARKS ON THE GENUS FLEMINGITES. By W. CARRUTHERS, F.L.S., F.G.S. (PLATES V. AND VI.) THE Placsist of a few specimens of coal and a consider HE specimens placed in my hands by Mr. N. Plant from Rio able number of a highly ferruginous shale. The coal contains no re cognizable fossils, but they abound in the shale. The substance of the plants is converted into a brittle coal, that possesses no structure, and exhibits the form only of the organism, but the superficial structure and the venation is often so beautifully preserved on the surface of the shale, when the coal is removed, that the nature of the fossils is very clearly exhibited. I have, thus, been able to determine with precision three species, and to recognise more vaguely a number of other forms, which, however, it would be injudicious, until additional material is obtained, to name or describe from the specimens in my possession. All these forms, as far as they can be determined, and certainly the three well-preserved species, belong to Paleozoic genera, species of which occur in the Coal-measures of Britain. We are thus enabled with certainty to refer the Coal-fields of the province of Rio Grande do Sul to the Carboniferous period, although the coal itself has more the aspect of being the product of a Secondary formation. The three species which I propose describing in this paper are new forms belonging to the genera Flemingites, Odontopteris, and Noeggerathia. The most interesting of the three is the species of Flemingites, of which there are a large series of specimens of the stems and foliage, as well as of the detached sporangia. The characters of the species are as follows: Flemingites Pedroanus, sp. nov. Stem lepidendroid, scars small, obovate, without any markings; base of the petiole permanently attached to the stem; leaf slender, linear; venation parallel. Fruit a cone (?) the scales of which support numerous roundish sporangia. I have, at the suggestion of Mr. Plant, associated with this interesting fossil the name of Dom Pedro II., Emperor of Brazil, who has on many occasions rendered such substantial aid to scientific investigators, as to have laid students of science under a debt of gratitude to him. Some years ago (GEOL. MAG. Vol. II. p. 433) I established the genus Flemingites on the fragment of a cone which exhibited the relation of the small round sporangia so abundant in many coal-beds to their supporting organisms. There were no indications, in the only specimen I then had, of the plant on which the cone was borne, though it was evident from the structure and arrangement of the parts that it was the fruit of a form of Lepidodendron. I have since seen more perfect specimens from Burdie House in the collection of the British Museum, and from the Newcastle Coal-field belonging to Mr. J. Duff of Etherly. In my recent examination of the rich collection of Coal plants in the Newcastle Museum I found that the specimen figured in Lindley and Hutton's Fossil Flora, plate x. fig. 1, as a form of Lepidostrobus variabilis is really a specimen of Flemingites gracilis. In passing, I may say that this supposed species was made the receptacle for all indistinct and badly preserved specimens of such cones; the variable appearance of the specimens arising from their belonging to different species, and even, as it now appears, to different genera. In all the specimens, however, of Flemingites which I have examined I have seen no indication of the branch or tree on which they were supported, and the characters of the genus have been consequently confined to those of the cone. It is not a little interesting that the materials for completing our acquaintance with the fossil should be brought from South America,-a continent which, as far as I know, has not hitherto yielded any paleozoic fossil plants. The examination of the plate and of the description given will show, however, that the one organ wanting in the specimens from Brazil is the cone on which to a considerable extent I founded the genus. The sporangia abound, and though the co-relation of these organs with the lepidodendroid stem depends not upon direct observation but upon induction, yet that induction is so conclusive that it appears to me to place the matter beyond doubt. The small round sporangia belong, as far is known either to Sigillaria or Flemingites. They abound in these Brazilian shales, and the only plants associated with them to which they could belong is that which is described in the diagnosis of the species. The arrangement of the leaf scars and the form of the leaf conclusively establish that this is not a Sigillaria Among Mr. Plant's small collection there are over twelve different specimens of the stem, with numbers of sporangia scattered over the surface of the fragments on which they are preserved, and in one specimen several sporangia occur among the mass of true leaves which remain attached to the end of the branch, though not related to them as in the described cone of Flemingites. The spiral arrangement of the leaves on these stems also agrees with the arrangement of the fruit-bearing leaves on the cone, so that there can be no doubt that the stems belong to Flemingites. They have the ordinary aspect of the stems of Lepidodendron, the scars being arranged in a spiral order. There are nevertheless points of considerable importance by which the two forms can be distinguished. The scars are small, approaching in size and form those of Lycopodiolites cordatus, Sternb. (Flora d. Vorwelt, tab. lvi. fig. 1), from Yarrow in Durham, a fossil which has been overlooked by subsequent authors, except that Professor Morris, who never overlooks anything, records it in his Catalogue of British Fossils under the name of Lycopodites cordatus. In the Brazilian fossil the scar is not cordate, but perfectly rounded on its upper margin (see enlarged scars, Pl. V. Fig. 11). But the most important character in respect of the scar is that it presents no impressions from an articulating surface like what is seen in Lepidodendron. This arises from the fact that the bases of the petioles permanently invested the stem, the leaves disarticulating at a line about a quarter of an inch along the petiole from the stem surface. A somewhat similar structure is described by Corda in his genus Lomatophloyos 1 Prof. Morris has shown me specimens of Corda's L. crassicaule from English strata, and I have a second species from the beds of volcanic ash in Arran to which I have given the name of L. Wunschianus, after my friend Mr. E. A. Wünsch, of (Beitrage, p. 17). In the only species described by Corda, L. crassicaule, the bases of the leaves are larger and proceed from the stems in a line having the same direction as that of the leaves, which are articulated to them. In these stems from Brazil, the permanent slender bases of petioles (Pl. V. Figs. 1, 7, 8), shortly after leaving the stem, take an ascending direction parallel to the surface of the stem, and pass somewhat over the base of the petiole above before the leaf is given off. In the fresh plant the imbricated petioles would give a continuous surface parallel to the circumference of the stem. Although this appearance is not exhibited in any of the specimens from Brazil, it is clearly shown in a species from Cape Breton Island, for which I am indebted to Mr. Edgecombe Chevallier. A specimen of the same species is figured by Geinitz under the all-absorbing name of Lepidostrobus variabilis, Lindl. (Versteinerungen, tab. ii. figs. 1, 3, 4). In these figures the stem is shown densely covered with the permanent petioles, and at B' fig. 1, the imbricated surface of the end of the petioles is shown, while at the margins of the specimen the relation of the leaves themselves to the petioles is also clearly shown. It would be rash to affirm that this structure is peculiar to the genus Flemingites, but future discoveries may show that it is. In Flemingites Pedroanus the curve of the leaf is the reverse of that of the permanent petiole, being bent outwards and downwards. The impressions of the leaves on the shale is, in some specimens, so perfect, that even the venation can be seen; and this is parallel, as is shown in the magnified portion on Plate V., Fig. 6. The sporangia are considerably smaller than those of F. gracilis, as may be seen by a comparison of figure 4, Plate V., with figures 4, 5, 6 of Plate XII. GEOL. MAG. Vol. II., 1865, these various figures being drawn to the same scale. The tri-radiate ridge on the under surface, by which the sporangia were attached to the supporting shale, is more delicate, and is produced further towards the circumference than in the British species. The contents of one of the sporangia in a compacted condition, yet with indications of their original granular state, is shown in Fig. 2. The mineral condition of the sporangia is like that of the specimens I have examined from our British deposits, and which Prof. Morris has described as "neither bituminized nor mineralized, but in a state of brown vegetable matter." The discovery by Brongniart of a cone containing microspores in the sporangia of its upper portion, and macrospores in those of its lower portion, has led me to re-examine the nature of the contents of the sporangia of these fossils, and somewhat to alter the opinions I expressed in the paper on Flemingites, which has been referred to. While the size of the individual plant is very variable among species of the same natural order of Cryptogamia, that of the organs of reproduction, the spores, is remarkably uniform. The spore of Glasgow, to whom science is indebted for the discovery of this very interesting deposit of coal plants. I may add to the synonymy of Corda's species, Cycadium cyprinopholis, Guillard Cycadites cyprinopholis, Morris, a fossil from the Coal-measures of the centre of France, hitherto considered to be a Cycadean stem. = 1 Comptes Rendus des Séances de l'Académie des Sciences, Août 17, 1868. Trans lated in the Journal of Botany, Jan. 1869. |