PART I.
FOSSIL FLORA.
Plates I. to XXXIII. inclusive.
DESCRIPTION OF THE PLATES.
* * * * *
PLATE I.
(Plates I. to IX. inclusive are from Parkinson's Organic Remains.)
Fossil Woods and Leaves.
Fig. 1. Fossil coniferous wood, from a bed of clay at Blackwall. This wood is simply bituminized, and has undergone no other mineral transmutation; it is in the usual condition of wood in peat-bogs.
Fig. 2. A piece of bituminous wood, containing _Mellite_, or Honey-stone (_honigstein_ of Werner), the yellow crystallized substance in the middle of the specimen. It is a fossil resin, allied to amber: from Thuringia.
Fig. 3. Carbonized coniferous wood, from the so-called "Bovey Coal" formation of Devonshire.
Fig, 4. A piece of calcareous wood, showing very distinctly the ligneous structure on the surface.
Fig. 5. Lignite, or carbonized wood, in clay; the cracks or fissures in the wood are filled up with white calcareous spar. Specimens of this kind are common in many argillaceous strata, as well as in limestone.
Fig. 6. A fragment of shale, covered with the imprints of the leaf-stalks that have been shed. It is a species of _Lepidodendron_. See description of Plate XXVI.
Fig. 7. This fossil vegetable is part of the stem of a tree; and possibly of a species of _Sigillaria_.
Fig. 8. Portion of a nodule of ironstone, enclosing some pinnules or leaflets of a beautiful fern (_Neuropteris_): from Coalbrook Dale, Shropshire.
PLATE II.
Petrified Woods.
Fig. 1. Silicified bituminized wood; probably from New Holland.
Fig. 2. Silicified root of a coniferous tree, (_Rhizolithes_, of the early collectors,) "resembling in structure that of the larch."--_Mr. Parkinson._
Fig. 3. A similar example of silicified bituminous wood, or root.
Fig. 4. Fossil coniferous wood, a longitudinal section.
Fig. 5. Another section of the same fossil wood.
Fig. 6. "Petrified larch-tree," from Mount Krappe in Hungary.
Fig. 7. Silicified bituminous wood.
Fig. 8. "Jasperized wood, resembling in structure that of the hazel."--_Mr. Parkinson._
Fig. 9. Silicified coniferous wood; apparently a dried and withered mass, before it underwent petrifaction.
Fig. 10. Silicified wood, having a cavity lined with mammillated chalcedony; appearing as if the silex had percolated through the substance of the mass, and had slowly oozed into the hollow.
Fig. 11. Silicified bituminous wood. In this specimen the siliceous matter occurs in yellow semi-pellucid globules; the colour is supposed to have been derived from the bitumen.
The silicified woods delineated above, belong to the division which Mr. Parkinson denominated opaline; he conceived their peculiar characters to have resulted from an infiltration of fluid silex into the ligneous tissue, which, having previously undergone bituminization, was in a permeable state; hence originated the conchoidal fracture and peculiar resinous lustre which these specimens exhibit.
The specimen, fig. 7, Mr. Parkinson describes as corroborating the opinion that the ligneous tissues were converted into a bituminous substance, and subsequently impregnated with siliceous matter. "In that fossil there is a knot of wood which differs not the least in appearance from that in a recent piece, but it is perfectly impregnated with opaline silex. Is it possible that the change this knot has suffered could have been effected by an abstraction of the greater part or of the whole of its constituent molecules, and a substitution of particles of a different nature? Its hardness and closeness of texture oppose an insuperable bar to the supposition: whilst the mysteriousness of the change is entirely dispelled by admitting of the softening operation of bituminization, and consequent admission of silex in a fluid state."--_Mr. Parkinson_.
PLATE III.
Petrified Stems and Leaves.
Fig. 1. A portion of the trunk of the fossil vegetable called _Stigmaria ficoides_ (of M. Alex. Brongniart); it is the root of a tree common in the coal deposits; see _Supplementary Notes_, Art. _Stigmaria_, p. 198, for a description of the nature and mode of occurrence of these fossils.
Fig. 2. Impressions of dicotyledonous leaves in travertine; a modern calcareous deposit; from Campania.[8]
[Footnote 8: Medals of Creation, vol. i. p. 193.]
Fig. 3. Part of the stem of a reed-like plant (_Calamites dubius_, Brongniart); from the coal deposits of Yorkshire. See description of _Calamites_.
Fig. 4. Appears to be a fragment of the stem of a species of _Lepidodendron_.
Fig. 5. Fragment of the leaf of a Cycadeous plant, from the oolite of Stonesfield. (_Zamia pectinata._)
Fig. 6. Portion of an ironstone nodule, split asunder, showing part of the terminal branch of a _Lepidodendron_, from Coalbrook Dale. See description of _Lepidodendron_.
Fig. 7. "A pebble that appears to have been partly enveloped in a leaf while in a soft state, which has produced the markings on its surface."--_Mr. Parkinson._
Fig. 8. "Ligniform pitchstone;" fossil wood having a resinous transparency; supposed by Mr. Parkinson to have originated from an intermixture of silex and bitumen; the internal part is opalized.
Fig. 9. Fragment of calcareous coniferous wood from the Lias of Charmouth, Dorsetshire: the vegetable structure is well preserved.
PLATE IV.
Fossil Fern Leaves.
Figs. 1, & 2. An ironstone nodule, split asunder, showing an inclosed fern-leaf (_Alethopteris lonchitidis_, of Sternberg); from the coal-beds of Newcastle.
Figs. 3, & 4. The corresponding parts of another nodule, containing a fern-leaf of a different kind (_Neuropteris_).
Fig. 5. A very beautiful fossil fern (_Cheilanthes microlobus_, of Göppert; _Sphenopteris_, of Brongniart); from the coal formation.
Fig. 6. A slab of coal-shale with fronds of ferns (_Alethopteris Serlii_, of Göppert); from Dunkerton.
Fig. 7. A beautiful fern (_Pecopteris_) in coal-shale; from Newcastle.
PLATE V.
Fossil Ferns and Stems.
Fig. 1. A beautiful delicate plant, belonging to a family of which numerous species occur in the coal deposits; named, from the stellular form of the foliage, _Asterophyllites_.
Fig. 2. A fern in coal-shale, from Yorkshire. (_Sphenopteris trifoliata_, of Artis.)
Fig. 3. Another species of star-leaf plant (_Annularia brevifolia_), from the coal of Silesia.
Fig. 4. A dicotyledonous leaf in sandstone, in a beautiful state of preservation; from the tertiary strata of Œningen.
Fig. 5. A frond of a remarkable species of extinct fern (_Cyclopteris orbicularis_, of Brongniart); from the coal of Shropshire.
Fig. 6. An elegant fern (_Pecopteris_), from coal shale; Newcastle.
Fig. 7. A delicate plant (_Sphenophyllum erosum_, vel _dentatum_, of Sternberg), with wedge-shaped pinnules, from the coal formation.
Fig. 8. Portion of a stem, flattened by compression, of a species of _Sigillaria_ (_Sigillaria tesselata_, of Brongniart). From the coal of Yorkshire.
Fig. 9. Fern (_Pecopteris oreopteridis_, of Brongniart); from the coal of South Wales.
Figs. 10, & 11. Two specimens of _Asterophyllites_ in ironstone nodules, from Coalbrook Dale. The white appearance is occasioned by a deposition of hydrate of alumina.
PLATE VI.
Fossil Fruits from Sheppey.
The greater number of the specimens here figured, are from the London clay of the Isle of Sheppey.[9]
[Footnote 9: For an account of the circumstances under which fossil fruits, &c. occur in that celebrated locality, see Medals of Creation, vol. ii.]
These fossils are strongly impregnated with pyrites (sulphuret of iron), and are liable to decompose after exposure to the air for a few weeks or months, even when placed in closed cabinets: when first found they are remarkably beautiful. An excellent work on the fossil fruits of the Isle of Sheppey, was commenced by J. S. Bowerbank, Esq. F.K.S. of Highbury Grove; but which, it is much to be regretted, was discontinued after only three numbers were published.
Fig. 1. Portion of a branch of a tree, completely mineralized by pyrites; it is the "pyritous fossil wood" of Mr. Parkinson.
Figs. 2, & 3. Vegetable substances, too imperfect to determine.
Figs. 4, 8, 9, & 13. The berries of an extinct genus of plants, (named _Wetherellia_, by Mr. Bowerbank, in honour of Mr. Wetherell of Highgate,) which, from their appearance when split asunder, are called by the local collectors, "coffee berries." The natural affinities of these fossils are not determined.
Figs. 5, 6, & 7. The fruit or seed-vessel of a palm allied to the recent Nipa, a native of the Molucca Islands; the fossil is therefore named _Nipadites_.[10] See the next Plate.
[Footnote 10: Medals of Creation, vol. i. p, 180.]
Figs. 10, & 12. Fossil fruits of plants belonging to the Cucumber tribe (hence named _Cucumites_, by Mr. Bowerbank).[11]
[Footnote 11: Plate xiii. of Mr. Bowerbank's work on the Fossil Fruits of the London Clay, contains numerous figures of Cucumites.]
Fig. 11. A transverse section of Fig. 16.
Figs. 14, 18, 24, & 26, are varieties of Cucumites.
Fig. 16. Calcareous wood from Oxfordshire.
Fig. 19. Wood mineralized by copper (Cupreous fossil-wood of Parkinson), from Souxson, in Siberia.
Fig. 18. Fossil fruit resembling the seed-vessels of plants of the genus _Cupania_ (_Amomocarpum_, of Brongniart; _Cupanoides_, of Bowerbank); M. Brongniart considers the original to have been related to the Cardamoms (_Amomum_).
Fig. 21. Probably a species of Cupanoides.
Figs. 20, & 22. Pericarp of a fruit; its affinities unknown.
Fig. 23. A piece of pyritous wood.
Fig. 25. A rolled specimen of _Nipadites_.
Figs. 24, & 26. Two fruits of plants of the Cucumber family (_Cucumites_).
Figs. 27, & 29. Specimens of the stems of a species of extinct Club-moss (_Lycopodites squamatus_); fossils of this kind are abundant in the pyritous clay of Sheppey.
Fig. 28. A fragment of silicified wood, rounded by attrition; from the gravel-pits at Hackney.
* * * * *
Figs. 15, & 17. I have purposely reserved the description of these fossils for this place, because notwithstanding their close resemblance to the aments or cones of a pine or larch, which led the earlier collectors to regard them as fruits, they do not belong to the vegetable but to the animal kingdom, being the hardened excrementitious contents (_Coprolites_) of the intestines of the fishes, with whose remains they are associated in the chalk.[12] The specimens figured are from Cherry Hinton, in Cambridgeshire; similar fossils occur in the Chalk and Chalk-marl of Sussex, Kent, &c.
[Footnote 12: See Medals of Creation, vol. i. p. 432; and Dr. Buckland's Bridgewater Essays, vol. ii. pl. 15.]
PLATE VII.
Fossil Fruits of Palms.
Figs. 1-5. Splendid specimens of one of the most remarkable of the fossil fruits that occur in the London clay of the Isle of Sheppey. The nut in its pericarp or husk is shown in fig. 1, the separate pericarp in fig. 2, and the nut itself in fig. 3. Figs. 4 and 5, represent another beautiful fossil of the same species.
These fossil fruits, which Mr. Parkinson considered as belonging to a species of Cocos, or Cocoa, and M. Brongniart referred to the Pandanus or Screw-pine, Mr. Bowerbank has demonstrated to be closely related to the recent _Nipa_, or Malucca Palm; a low shrub-like monocotyledonous plant, that inhabits marshy tracts near the mouths of great rivers, particularly where the waters are brackish.
Mr. Bowerbank has figured and described eleven species. The species represented in this plate is distinguished as _Nipadites Parkinsonis_: M. Brongniart had previously named it _Pandanocarpum Parkinsonis_.[13]
[Footnote 13: See an account of an "Excursion to the Isle of Sheppey," Medals of Creation, vol. ii. p. 897.]
The following is Mr. Bowerbank's description of these fossils:--
"The fruits of which the group I propose to name _Nipadites_ is composed, are known among the women and children by whom they are usually collected, by the name of '_petrified figs_.' The epicarp and endocarp are thin and membranous; the sarcocarp is thick and pulpy, composed of cellular tissue, through which run numerous bundles of vessels. The cells are about the 8/100th part of an inch in diameter. Nearly in the centre of the pericarp is situated a large seed, which, when broken, is found to be more or less hollow. It is frequently not more than half a line in thickness; but in perfect specimens it presents the appearance of a closely granulated structure, in which small apertures containing carbonaceous matter occasionally occur. The seed in _Nipadites Parkinsonis_, consists of regular layers of cells radiating from a spot situated near the middle of the seed, and apparently enclosing a central embryo.
"If the habits of the plants which produced these fossil fruits were similar to those of the recent _Nipa_, it will account for their amazing abundance in the London Clay of the Isle of Sheppey; which formation, from the great variety of fossilized stems and branches, mixed up with _asteria_, _mollusca_, and _conchifera_ of numerous marine and fresh-water genera, is strikingly characterized as having been the delta of an immense river, which probably flowed from near the Equator towards the spot where these interesting remains are now deposited."[14]
[Footnote 14: History of the Fossil Fruits and Seeds of the London Clay. Van Voorst, London, 1840.]
Figs. 6, 7, & 8. Specimens of a seed-vessel, or nut, of an unknown plant, often found in the strata of the coal measures. It is called _Trigonocarpum olivæforme_, from its general shape. From Leicestershire; it probably belongs to a plant of the Palm family.
PLATE VIII.
Petrified Stems and Woods.
Figs. 1-7, represent different sections and parts of some remarkably beautiful and interesting silicified stems of an extinct tribe of plants, related to the arborescent ferns, and which are found in considerable abundance at Chemnitz, near Hillersdorf, in Saxony. The name of _Psaronius_ is given to the genus by M. Cotta.
Figs. 1, 2, 5, 7, are _P. helmintholithes_; figs. 3, 6, _P. asterolithes_; figs. 5, 6, 7, are enlarged figures of the transverse sections of some of the vessels forming the vascular tissue.
From the stellular figure produced by transverse sections of the vessels, this fossil wood has received the name of "_Staarenstein_," or Starry-stone. In the time of Mr. Parkinson, the tubes now known to be the vessels of the vascular tissue, were supposed to have been produced by some boring or parasitical animals.
Fig. 4. Transverse section of a stem of calcareous wood from the Bath oolite.
Figs. 8, & 9. Calcareous fossil wood; the cylindrical cavities have been formed by the depredations of the ligniverous boring mollusk, the _Teredo_, and are now filled with translucent calcareous spar. This kind of fossil was called "_Lapis syringoides_" by the early collectors.
Fig. 10. Silicified wood; the perforations are supposed to have been occasioned by the depredations of boring mollusca: the cavities are filled with a white pellucid chalcedony.
PLATE IX.
Fossil Stems and Seed-vessels.
Fig. 1. The strobilus or cone of an extinct family of plants whose remains are very abundant in the coal strata, and which have largely contributed to the formation of the mineral fuel now become so indispensable to the necessities and luxuries of man. There are several kinds, and although there can be no doubt that they are the seed-vessels of the _Lepidodendra_ with which they are associated, yet but few species are identified with their parent trees. The specimen figured is the _Lepidostrobus ornatus_ of Lindley and Hutton. From the coal measures of Coalbrook Dale.
Fig. 2. One of the so-called "Petrified Melons" of Mount Carmel.
Figs. 3 & 4. An unknown fossil body; possibly a coral.
Fig. 5. A vertical section of one of the "_Petrified Melons_" from Mount Carmel. The fossil thus named by Mr. Parkinson appears to be merely a siliceous nodule, having a cavity lined with quartz crystals. There is, however, a legend rife among the barefooted friars of Mount Carmel, that has conferred a celebrity on these stones; it runs, that "on this spot was a garden well stocked with melons, and that the prophet Elias, who founded the monastery, once asking the gardener for one of his melons, he with churlish humour answered, they were not melons but stones: on which they were immediately changed into stones, and so remain to this day."
Figs. 6 & 7. Unknown vegetable fossils, highly metallic; fig. 6 appears to be a fragment of a cone.
Figs. 8 & 9, are nodules of pyrites, accidentally assuming the form of fungi; they are not fossils, but simply masses of inorganic mineral matter.
Fig. 10. Portion of the flattened stem of an extinct plant, from the coal measures of Yorkshire, whose affinities are uncertain; supposed to resemble the Yew-tree. It appears to be similar to the fossil named _Knorria taxina_ by Messrs. Lindley and Hutton in the British Fossil Flora. In that beautiful work,--the continuation of which is much to be desired,--the genus _Knorria_ comprises those fossil stems in which the projecting scars of the petioles are densely arranged in a spiral manner.[15]
[Footnote 15: Medals of Creation, vol. i. p. 161.]
PLATE X.
(Plates X. to XXXIV. inclusive, are from Artis's work on the Fossil Remains of Plants, from the coal formations of Great Britain.)
"Columnar Hydatica."
Under the name _Hydatica_, Mr. Artis has described two species of fossil plants, from the coal-mine near Wentworth, Yorkshire. The originals appear to have been aquatic plants, having a horizontal or creeping stem, sending up slender branches, which floated by their leaves on the surface of the water.
The generic characters are, "Stem, arborescent, jointed, branched; leaves, long, linear."
In the arrangements of Schlotheim and Brongniart, who consider only the construction of the leaves, these plants would belong to the genus _Poacites_.
The species figured is named _Hydatica columnaris_, or Columnar Hydatica. The stem is branched all the way up, and ends in a club-like head; the branches are numerous, simple, alternate, and covered with parallel hair-like leaves.
Fig. 1. The plant of the natural size, imbedded in coal-shale; fig. 2, a branch magnified, showing; the two linear series in which the leaves are arranged.
PLATE XI.
"Prostrate Hydatica."
A splendid specimen of another species of _Hydatica_, spread out on the surface of the coal-shale, as if expanded on the bosom of the lake in which it grew: the length of the original, a part of which only is figured in the plate, was eight feet, five inches.
This species is named by Mr. Artis, _Hydatica prostrata_. The stem is jointed, and slightly striated; the joints are formed with irregular sutures, whence arise tufts of linear leaves resembling those of our common grasses.
Fragments of this fossil plant are abundant in the roofs of several of the chambers whence the coal has been extracted, in Elsecar Colliery, Yorkshire.
PLATE XII.
"Slender Myriophyllite."
The fossil here figured seems to approximate very closely to the Hydatica; but Mr. Artis describes the plant under the generic name of _Myriophyllites_;--_M. gracilis_. The stem is herbaceous and slender, terminating in a point; it is thickly covered with hair-like leaves.
It was found imbedded horizontally, in detached masses, separated from the great mass of vegetable matter which covers the coal, by an intervening layer of shale. It is rarely met with in the same bed with other vegetables, but generally in solitary and thin strata, taking a horizontal position; so that by riving the shale which contains these plants, numbers of them are disclosed on the same surface. In its general aspect this fossil vegetable resembles the trailing roots of some aquatic plants.
PLATE XIII.
"Branched Calamite."
Long and large jointed stems, generally more or less flattened by compression, and bearing some resemblance to a cane or bamboo, are very abundant in the coal formations. Some of them attain many feet in length, and are of a corresponding magnitude in circumference. The original plants are supposed to have been related to the _Equisetaceæ_, or Mare's-tail, and not to the _Bambusiæ_, and other arborescent grasses. The stem is jointed, and longitudinally striated, having annular impressions at the articulations.
The present species (_Calamites ramosus_) has the stem arborescent and branched; the branches are cylindrical, striated, and inserted at the articulations of the trunk; the articulations of the branches are surrounded by a striated disk.
The stem has been found nine feet in length, and occurs both horizontally and vertically, in sandstone, in Leabrook Quarry, near Wentworth.
PLATE XIV.
"Doubtful Calamite."
These fossil stems are from the same sandstone quarry as the Calamite delineated in the previous plate.
They differ in some respects from the usual type of the genus, hence the specific name (_Calamites dubius_). The striæ are narrow, and have a fine groove running down the middle; the fifth or sixth articulation is surrounded by a double line of large globular indentations, one row belonging to each of the connected joints; these imprints have apparently been left by a zone of some organs which surrounded the articulations, and by its pressure left the indented frill, shown in the upper extremity of fig. 2.
These stems are generally found compressed, and from two to three feet in length. Their termination is unknown.
This species is figured by M. Ad. Brongniart in Hist. Veg. Foss. tab. 18, figs. 1-3.
PLATE XV.
"Pseudo-Bamboo Calamite."
(_Calamites pseudo bambusia_, of Sternberg. ---- _Suckovii_, of Brongniart, Hist. Foss. Veg. tab. 14.)
"This fossil was found in the clay which fills the fissures of a very fine grit, called by the workmen 'Delf,' that forms a stratum from twenty to twenty-five feet thick, in the quarry at Leabrook, near Wentworth, in Yorkshire. Immediately under this stratum there is a thin bed of very good coal; and at a considerable depth below this bed, there is a second layer of coal, eight feet thick, which is covered in particular places with immense masses of fossil plants."
The species here figured very closely resembles the Bamboos. The stem is arborescent, and marked with parallel linear strife, which are intercepted at the sutures; it is simple and cylindrical, and contracted at the articulations; it occurs five feet or more in length.
Fig. 1, represents part of the middle of a stem.
Fig. 2, shows the gradual upward diminution of the stem, and its pointed termination.
PLATE XVI.
"Short-jointed Calamite."
(_Calamites approximatus_, Sternberg. ---- ----, Brongniart, Hist. Veg. Foss. tab. 24.)
This species of Calamite is characterized by the shortness and number of the joints; these are intercepted by distinct articulations, and have small compressed tubercles, forming a studded row round the trunk. The articulations are about one-fifth the diameter of the stem apart. The tubercular studs, or warts, are probably the cicatrices of fallen leaves; they rise directly from the articulations, and not from the lower termination of the striæ, as in the species figured in the next plate.
The specimen was found imbedded horizontally in soft sandstone, at the bottom of the rock in Hober Quarry, near Wentworth.
Fig. 1, represents a portion of the upper part of the trunk, of the natural size, terminating at the top in a sharp compressed point.
Fig. 2. An outline on a reduced scale, to show the proportionate size of the stem.
PLATE XVII.
"Ornamented Calamite."
(_Calamites decoratus_, Artis. ---- ----, of Brongniart, Hist. Veg. Foss. tab. 14, figs. 1-5.)
In this species of Calamite the joints are short, and decrease in length towards the summit, where they terminate in an enlarged rounded head. The striæ are ornamented with tubercles at the bottom, close to the articulation. The striæ are broader, and the tubercles larger, towards the summit.
The stem is sometimes found two feet long, and from two to four inches in diameter.
The situation of the tubercles at the lower extremity of the striæ, is a striking feature of this species; and the termination of the summit of the stem is remarkable for its obtuseness.
The specimen is from Leabrook Quarry, Yorkshire.
PLATE XVIII.
"Transverse Sternbergia."
(_Sternbergia transversa_, of Artis. _Artesia_ ----, of Presl. Additions to Sternberg's _Flora der Vorwelt_.)
The stems known by the name of _Sternbergia_, (from Count Sternberg, the author of the Fossil Flora,) appear to be related to the Yucca, or to the Pandanus or Screw-pine.
Mr. Artis observes, that they bear considerable analogy to the stems of the _Stapeliæ_ of our gardens; but still, the external form, which Is the only character visible, does not furnish sufficient ground for their being positively referred to that genus. The stem is marked longitudinally with double keels or ridges, which terminate at different heights spirally round the stem, and have small tubercles at their terminations. There are likewise slight annular depressions, mostly distinct, but in some places two or more unite.
The stem is straight, simple, and cylindrical, and is compressed towards the summit. It is sometimes found six feet in length, and from one to four inches in diameter. It is generally coated with a carbonized bark.
Fig. 1, shows a portion of the stem of the natural size.
Fig. 2. The upper extremity, in which the tubercular terminations of the double keels or ridges are seen at A, B.
Found associated with Calamites in the clay-bind of Leabrook Quarry.
PLATE XIX.
"Fibrous Sigillaria."
(_Rhytidolepis fibrosa_, of Artis.)
Stems more or less flattened, with the external surface longitudinally furrowed, and uniformly ornamented with rows of deeply imprinted symmetrical figures, disposed with much regularity, are among the most abundant vegetable remains in the coal formation. These are named _Sigillariæ_, from the Latin word _sigillum_, signifying a _seal_, in allusion to the extreme regularity of the imprints on the surface. When found in an upright position, at right angles to the plane of the stratum, the original cylindrical form of the tree is commonly preserved; and many examples are now known of groups of erect Sigillariæ, with their roots extending into the surrounding clay or sandy loam; the roots proving to be the fossil bodies called _Stigmariæ_, which were formerly supposed to be a distinct family of aquatic plants.[16] The first discovery of this highly interesting and unexpected fact was made by Mr. Binney.[17]
[Footnote 16: Dr. Buckland's Bridgewater Essay, vol. i. p. 476.]
[Footnote 17: See "Supplementary Notes, p. 198."]
The specimen figured was found in an erect position in the sandstone of a quarry at Rowmarsh, near Rotherham in Yorkshire.
The stem is simple, the furrows small and wavy, impressed with dots on the ridges. The cicatrices are ovate, subpentagonal, with the lower angles rounded, having a single gland near the lower extremity. The stem is three feet long, and four inches in diameter.
The transverse section, as seen in fig. 1, shows traces of a double concentric ring, as if produced by internal structure. Fig. 2, displays the equality of the stem throughout its entire length, and its abrupt termination. In fig. 3, is seen the cicatrix with its single gland, for the attachment of the petiole or leaf-stalk. Fig. 4, indicates the undulating line of the top of the ridge.
"The originals of these fossils are supposed by M. Ad. Brongniart to have constituted a peculiar family of coniferous plants, now extinct, which probably belonged to the great division of gymnospermous dicotyledons. In their external forms they somewhat resembled the Cacteæ or Euphorbiæ, but were more nearly related by their internal organization to the Zamiæ or Cycadeæ. The leaves and fruits of these trees are unknown, for no satisfactory connexion has been established between the stems, and the foliage and seed vessels with which they are sometimes collocated."[18]
[Footnote 18: Medals of Creation, vol. i. p. 138.]
PLATE XX.
"Sigillaria."
(_Euphorbites vulgaris_, of Artis.)
This species is characterized by the remarkable fish-like form of the cicatrices left by the base of the leaf-stalks, and by the rapid tapering of the upper part of the stem, as shown in the reduced figure 1, which represents a specimen nine feet long, five feet in circumference at the base, and only twenty-one inches in circumference at the upper end.
The ridges, which at the superior extremity are simple and narrow, and parted only by a single line, become at the lower part of the stem wide and flat, and are separated by a groove of equal breadth, as seen in fig. 3, which is taken from B, fig. 1.
Fig. 2, represents a portion towards the upper end, at A, fig. 1; and exhibits the different appearance of the bark, and the under surface, when the cortical investment is removed; the imprints in each case differing very much in appearance.
The specimen from which the drawing was taken, was from a sandstone quarry near Altofts, in Yorkshire. In one of the abandoned chambers of the upper Elsecar coal-mine, seven trunks of this tree were suspended freely from the roof, the largest of which was eight feet in circumference.
PLATE XXI.
"Ficoid Stigmaria."
(_Stigmaria ficoides_, of M. Brongniart, Hist. Veg. Foss. tab. 17, figs. 5, 6. _Ficoidites furcatus_, of Mr. Artis.)
The fossil trunks or stems called _Stigmariæ_, or _Variolæ_, (from the pits or areolæ with which they are studded,) occur as abundantly in the coal formation as the _Sigillariæ_, of which tribe of plants unequivocal proof has at length been obtained that they are the roots. These bodies are more or less regularly cylindrical, and vary in length from a few inches to fifteen or twenty feet, the largest being several inches in diameter. Their surface is covered with numerous oval or circular depressions, in the middle of each of which there is a rounded papilla, or tubercle. These variolæ are disposed round the stem in quincunx order. When these roots are broken across, a small cylindrical core or pith is exposed, which extends in a longitudinal direction throughout the stem, like a medullary column. This central axis, which is often separable from the surrounding mass, is composed of bundles of vascular tissue disposed in a radiated manner, and separated from each other by medullary rays. This internal organization presents the same correspondence with that of the stems of Sigillariæ, as does the structure of the roots of a dicotyledonous tree with that of its branches and stems.
The Stigmariæ are almost invariably present in the bed called the "Under Clay," which underlies the coal, and when observed in this situation, long tapering sub-cylindrical fibres are found attached to the tubercles; and these processes or rootlets are often several feet in length. Their form and mode of attachment are shown at C, D; the rootlets terminate in bifurcations, as seen at A, B.
The specimen here figured is part of a root nearly six feet long, and three inches in diameter; some of the rootlets were two feet long. It is imbedded in shale; from Elsecar colliery.[19]
[Footnote 19: A Stigmaria with rootlets, many feet in length, is placed over the doorway in the room devoted to fossil vegetables in the Gallery of Organic Remains in the British Museum.]
PLATE XXII.
"Warty Stigmaria."
(_Stigmaria ficoides_, Brongniart. _Phytolithus verrucosus_, Martin's Petrificata Derbiensia, Pl. II. _Ficoidites verrucosus_, of Artis.)
In this species of Stigmaria the tubercles vary considerably in size, and give a verrucose, or warty, aspect to the surface. The specimen figured on a small scale, fig. 2, and a portion of the natural size, fig. 1, was between five and six feet in length, and four inches in diameter. A groove visible on the external surface indicates the inner axis, which by compression has been pressed from its natural central position; see fig. 2, A, B, C, D: figs. 6, 7, 8, 9, show in the corresponding transverse sections the position of this body.
The mode of attachment of the rootlets to the tubercle on the main root, is represented fig. 5. Fig. 3, exhibits the characters of the two kinds of variolæ, or tubercles.
When Dr. Buckland's Bridgewater Essay was published, the true nature of these fossil remains was unknown. It was supposed by Messrs. Lindley and Hutton, that the original was an aquatic plant, having a short dome-shaped trunk, from which radiated numerous long horizontal branches; and that when the plant was perfect, and the branches floating on the water, its appearance resembled that of an Asterias.[20] This dome-shaped trunk is now known to be merely the base of the stem of the tree. See _Supplementary Notes_, art. _Stigmaria_.
[Footnote 20: Dr. Buckland's Bridgewater Essay, vol. ii. p. 95.]
PLATE XXIII.
"Great Stigmaria."
(_Stigmaria ficoides_, of Brongniart. _Ficoidites major_, of Artis.)
The fossil here represented is a fragment of a Stigmaria having larger tubercles than the species previously described. The tubercles are oval at the base, somewhat compressed, longitudinally farrowed at the top, with a pit in the furrow.
This root is from five to six inches in diameter; the axis is seen near the compressed side, in the transverse section at the bottom of the figure.
From a sandstone quarry, near Rotherham, Yorkshire.
The specimen figured by Mr. Parkinson, _ante_, Plate III. fig. 1, appears to be the fragment of a Stigmaria of this kind in ironstone: the internal axis is seen in the transverse section pressed from its natural position to near the outer surface.
PLATE XXIV.
"Crested Aspidiaria."
(_Aspidiaria cristata_, of Presl. _Sigillaria appendiculata_, Brongniart. _Aphyllum cristatum_, Artis.)
The fossil here represented is part of the stem of a tree nearly forty feet long, and two feet in diameter, found imbedded in sandstone at Banktop, Yorkshire.
The cicatrices of the petioles are obovate, and have a central oblong crest or ridge; the interstices form deep angular furrows.
The stems with this type of sculpturing, are supposed to belong to a group of extinct vegetables, which held an intermediate place between the Sigillariæ, previously described, and the Lepidodendra; together with the latter, and certain true Coniferæ and arborescent ferns, these trees appear to have constituted the principal forests of the Carboniferous epoch.
PLATE XXV.
"Frondose Megaphyton."
(_Megaphyton distans_, of Lindley and Hutton's Fossil Flora of Great Britain.)
Very large stems not channelled, with regular cicatrices of great size, arranged longitudinally, occur in the sandstone and grits of the Carboniferous formation, and are supposed to belong to a tribe of extinct plants, more nearly allied to the arborescent ferns of our tropical climes, than to any other existing trees.
The specimen figured is part of a stem ten feet in length, from a quarry near Rowmarsh in Yorkshire.
This stem has a coarse fibrous surface, furrowed longitudinally; the cicatrices left by the shedding of the leaves are of a horseshoe shape with the points directed upwards.
This group of stems has been separated by writers on fossil botany into several genera, as _Bothrodendron_, _Ulodendron_, &c.[21] In some of these the scars are five inches in diameter.
[Footnote 21: See Dr. Buckland's Bridgewater Essay, plate 56.]
There are many fine examples of these fossils in the British Museum.
PLATE XXVI.
"Lepidodendron, or Scaly-tree."
(_Aphyllum asperum_, Rough Aphyllum, of Artis.)
"The Lepidodendra (Scaly-trees) are a tribe of plants whose remains abound in the Coal formation, and rival in number and magnitude the Calamites and Sigillariæ previously described. The name is derived from the imbricated or scaly appearance of the surface, occasioned by the little angular scars left by the separation of the leaves. Some of these trees have been found almost entire, from their roots to the topmost branches. One specimen, forty feet high, and thirteen feet in diameter at the base, and divided towards the summit into fifteen or twenty branches, was discovered in the Jarrow coal-mine, near Newcastle.[22]
[Footnote 22: Wonders of Geology, sixth edition, vol. ii. p. 722.]
"The foliage of these trees consists of simple linear leaves, spirally arranged around the stem, and which appear to have been shed from the base of the tree with age. The markings produced by the attachment of the leaves are never obliterated, and the twigs and branches are generally found covered with foliage. The originals are supposed by M. Adolphe Brongniart, notwithstanding their gigantic size, to have been closely related to the Lycopodia, or Club-mosses."[23]
[Footnote 23: Medals of Creation, p. 144.]
Associated with the stems of Lepidodendra, and oftentimes imbedded in masses of their foliage, and in some instances attached to the extremities of the branches, are numerous oblong or cylindrical scaly cones, garnished with leaves: an imperfect specimen is figured in Plate IX. fig. 1, and the vertical section of another in Plate III. fig. 6. These cones have received the name of _Lepidostrobi_ (Scaly-cones), and are the seed-vessels or fruits of the Lepidodendra.[24]
[Footnote 24: See Medals of Creation, p. 147, and lign. 31, p. 149.]
These fossils often form the nuclei of the ironstone nodules from Coalbrook Dale, and are invested with a pure white hydrate of alumina; the leaflets, or more properly bracteæ, are often replaced by galena, or sulphuret of lead, giving rise to specimens of great beauty and interest, as examples of the electro-chemical changes which these fruits of the carboniferous forests have undergone.
The fossils figured in this Plate, are portions of a stem eleven feet in length, from near Hoyland, Yorkshire. Fig. 1, is from the upper part, and shows the carbonized scales attached; fig. 2, represents part of the lower end, in which the scales are decorticated, from the adhesion of the bark to the surrounding shale.
A. Shows the cicatrix, with its transverse gland that connects the scale, in the upper part of the trunk.
B. Exposes the interstice between the scales in the lower portion of the stem.
C. A section of the hollow cicatrix.
PLATE XXVII.
"Lychnophorite."
(_Lychnophorites superus_, of Artis.)
The fossil figured under the above name by Mr. Artis, is part of a large branch of a tree, the surface of which is covered with the cicatrices of leaf-stalks, as in the Lepidodendron. The form of the cicatrix and point of attachment is shown at B; figure A, is the restored outline of a leaf.
"Dr. Martins refers the fossil plants of this type to a recent shrubby genus of syngenesious plants, which cover the plains of Brazil, and which he names _Lychnophora_, whence he formed this fossil genus, by changing the termination to _ites_, according to the common usage."--_Artis._
The specimen represented is in sandstone, from Swinton Common, near Rotherham, Yorkshire.
This tree seems to be closely allied to the Lepidodendra.
PLATE XXVIII.
"Eared Neuropterite."
(_Neuropteris auriculata_, Brongniart. Hist. Veg. Foss. tab. 66. _Filicites Osmunda_, of Artis.)
The general aspect of this beautiful filicite very much resembles that of our well-known flowering fern, the elegant _Osmunda regalis_; the auriculated or one-eared base of the lanceolated leaflets forms, however, a distinguishing character. It belongs to the genus _Neuropteris_ (nerved-leaf fern) of M. Brongniart, which comprises many species of delicately-veined ferns: the veins in this fossil plant are very fine, arched, and rise obliquely from the base of the leaflet.
The leaflets are often found detached, and in many instances, though completely carbonized, are so firm, and so slightly attached to the shale, that they may be separated by a pair of forceps: when removed, their impression remains on the stone, as is shown in the light-coloured part of the figure 2; the form and distribution of the rib, and nervures or veins, are seen in fig. 3.
From Elsecar colliery.
PLATE XXIX.
"Trifoliate Sphenopterite."
(_Sphenopteris trifoliata_, Brongniart, Hist. Veg. Foss. tab. 53, fig. 3. _Filicites trifoliatus_, of Artis. _Cheilanthites_; from its supposed analogy to the recent genus _Cheilanthes_. Göppert. _Trans. Academy of Bonn_.)
This is a rare species of fern from the coal shale of Yorkshire, Elsecar Colliery. It has the leaf or frond tripinnate; the pinnæ, lobes, or wings, alternate with an odd one; the leaflets are ternate, with roundish, convex lobes.
This plant has been referred to the tropical ferns, and is nearly allied to the genera _Davallia_, or _Cheilanthes_; but from the almost general absence of the organs of fructification in fossil ferns, it is impossible to refer them with any certainty to living genera. It belongs to the Sphenopteres, or wedge-shaped-leaf ferns, of M. Brongniart.
A, shows the cast or matrix of the under side of the leaf; B, the upper side in relief.
PLATE XXX.
"Milton Filicite."
(_Pecopteris Miltoni_, Brongniart, Hist. Veg. Foss. tab. 114, _Filicites Miltoni_, Artis.)
This exquisite specimen exhibits part of two leaves attached to the stem, the under surface of the fronds, on which the fructification is beautifully displayed, being exposed. The frond is tripinnate, the stipes large and strong, the leaflets linear with the tip rounded. The fructification is arranged in lines near the margin; but slight traces of the venation of the leaflets are distinguishable.
From Milton, in Yorkshire.
PLATE XXXI.
"Plumose Pecopterite."
(_Pecopteris plumosa_, Brongniart, Hist. Veg. Foss. tab. 121. _Filicites plumosus_, Artis.)
This elegant fern is characterized by the plumose or wavy character of the stipes or stems of the fronds, which are tripinnate; the leaflets are lanceolate and sessile,--that is, are closely attached by their base, without a stalk. The fructification is seen disposed near the margins of the leaflets on the left hand upper part of the specimen.
From the same locality as the last.
PLATE XXXII.
"Decurrent Filicite."
(_Alethopteris decurrens_, of Göppert. _Pecopteris heterophylla_, Lindley and Hutton, tab. 38. _Filicites decurrens_, of Artis.)
The drawing represents but a small portion of the specimen, which indicated a plant of gigantic size.
"The leaf or frond of this fern is very large, tripinnate or quadripinnate; the stipes is broad and undulated; the leaflets are sessile, linear-lanceolate; the ribs pinnate, the secondary ribs perpendicular to the main rib; the first leaflet on the superior side of the pinnule adheres by its side to the rachis."--_Artis._
This fern, which closely resembles some recent species, (_Pteris aurita_,) occurs in great abundance in the shale at Alverthorpe near Wakefield. Notwithstanding the profusion with which the foliage of many kinds of ferns is distributed throughout the coal formation, the undoubted stems of tree-ferns are so rare, that it may admit of question whether some of the leaves which from the analogy of their structure to recent forms have been referred to the ferns, may not have belonged to the stems of unknown trees with which they are associated in the strata; for as, in the animal kingdom, distinct types of living organisms are often found blended in the extinct races, so in the vegetable, it is possible, that foliage and stems, of apparently discordant types, may have belonged to the same extinct species or genus of trees. This problem can only be solved by diligent and continued research in the richest localities of coal-plants.
M. Brongniart remarks that every bed of coal is the product of a special vegetation, often different from that which preceded, and that which followed it. Each bed thus resulting from a distinct vegetation, is characterized by the predominance of certain impressions of plants, and the experienced miners distinguish in many cases the beds they are working, by their practical knowledge of the plants that prevail.
The same beds of coal, and the deposits which cover it, ought therefore to contain the different parts of the plants that were living at the period of its formation; and by carefully studying the association of these different fossils, forming thus little special floras, generally of but few species, we may hope to acquire data by which we may advance the means of reconstructing the anomalous vegetable forms of the ancient world. M. Brongniart strongly urges attention to this circumstance in the examination of the coal strata, with the view of determining the identity of the scattered leaves, stems, and fruits, in any particular stratum. By such a procedure, much addition would be made to our knowledge of the entire structures of many of the fossil plants of which we now only know the fragments. Thus we may hope to ascertain the foliage of the Sigillariæ, the roots of which, by a similar method, have but recently been determined to be the fossils called _Stigmariæ_.
PLATE XXXIII.
"Carpolithe, or Fossil Seed-vessel."
(_Carpolithus marginatus_, of Artis.)
The carbonized husks or shells of nuts, and other carpolithes, or seed-vessels, are not unfrequently met with in the coal and coal-shale. In the slab of shale figured, there are three specimens of an oval nut, B, C, which is striated longitudinally. These are associated with other vegetable remains, among which part of a Lepidostrobus, the supposed cone or strobilus of a species of Lepidodendron (see description of Plate IX.), is conspicuous at a.