Chapter 12

[161]Petrifactions, p. 52.

ThePalmacites carbonigenusof Corda, and other supposed palm-trees of the Coal formation, are regarded by the same eminent botanist as essentially differing in structure from this family, and belonging to an extinct tribe of exogens.

That a large proportion of the exogenous stems found inthe Tertiary deposits are true palms, there can, however, be no doubt, for the foliage and fruit, which are occasionally associated with them, confirm the inference drawn from the characters of the trunks.

FOSSIL PALM LEAVES.

Stems, leaves, and fruits of Palms have been discovered in the Paris basin, by M. Ad. Brongniart (Bd.pl. lxiv. p. 515); and silicified trunks in many other places on the Continent; but no fossils of this kind surpass in beauty and interest those which are found in the West Indies. A slice of a silicified stem from Antigua is represented, as seen by reflected light, inPlate V. fig. 1; it admirably displays bundles of vessels imbedded in cellular tissue.

Silicified stems of monocotyledons, related to the Palms, are very widely distributed, and have been collected among mammalian remains in Ava, and in the Sub-Himalaya mountains.

Fossil Palm-leaves.—The pinnated and fan-shaped leaves of the Palms are so peculiar as to be easily recognized in a fossil state. Though many specimens have been found in the tertiary strata of the Continent, but two or three examples have been met with in England. The first discovered British specimen is in my cabinet, and was obtained by Mr. Fowlstone, of Ryde, from the fresh-water limestone of Whitecliff Bay, in the Isle of Wight. It is thirteen inches in length, and eleven in width: fresh-water shells and plants are imbedded with it. It is figured in Geol. I. of Wight,2d edit.p. 431. This species (Palmacites Lamanonis) occurs also at Aix in Provence, in great perfection, associated with Insects, Fishes, fresh-water shells, &c. (Wond.p. 260.Petrif.p. 62).

Twelve species of palm-leaves are enumerated by M. Unger, from the Tertiary deposits of the Continent. One species has been found in the Chalk formation of Silesia; the most ancient strata in which the remains of undoubted palms have as yet been observed.

The fossil palm-leaves of the pinnated form are namedPhœnicites,[162]and examples occur in the Tertiary grits of Puy en Velais, I am not aware that leaves of this type have been found in England: diligent research in our tertiary leaf-beds (at Whitecliff Bay, Alum Bay, Bournemouth, Wareham) will probably sooner or later discover them. The leaflets have a well-marked median nerve, with fine nervures running parallel with it; a character by which the foliage ofPhœnicitesmay be distinguished from that of the Cycadeæ.

[162]FromPhœnix dactylifera: the Date-Palm.

Fossil Fruits of Palms.—Although certain fruits found in the coal-measures have been referred to the palm-tribe by M. Unger, Dr. Lindley, and other botanists, M. Brongniart is of opinion that no such identification can be established; the same remark applies to the Carpolithes from the Oolite; in fine, the Tertiary deposits have alone yielded fruits that can be unquestionably referred to plants of this order. The most productive British locality of fossil fruits of Palms, and of many other vegetables, is the Island of Sheppey; and I purpose describing in this place, not only the remains of this family, but also of the other plants associated with them.

FOSSIL FRUITS OF THE ISLE OF SHEPPEY.

Fossil Fruits of the Isle of Sheppey.—This little island, which is situated in the mouth of the Thames, is entirely composed of the London Clay, with bands of septaria. On the north, there is a range of cliffs, about two hundred feet high, which is being continually undermined by the waves, and large masses of the clay are thrown down, and innumerable fruits, seeds, branches and stems of trees, and other fossils, are exposed on the strand at low-water. The vegetables are strongly impregnated with iron pyrites, and as this mineral speedily decomposes when exposed to the atmosphere, the choicest examples often fall to pieces,even when preserved in the cabinet.[163]The nodular masses of indurated clay, termed septaria, contain the best preserved and most durable fossils. The fossil fruits, or carpolithes, occur in such profusion, that a large collection can easily be made; they comprise several hundred species, few of which have been scientifically investigated.[164]

[163]Mr. Bowerbank, who possesses an unrivalled collection of these fruits, keeps them in stopper-bottles filled with water, placing the different species separately, and labelling the phials. I have successfully employed mastic varnish, first wiping the specimens dry, and removing any saline efflorescence by means of raw cotton, and then brushing in the varnish with a stiff hair-pencil.[164]See vol. ii. Excursion to the Isle of Sheppey.

[164]See vol. ii. Excursion to the Isle of Sheppey.

Mr. Parkinson has given admirable figures of several of the Sheppey fruits, particularly of the large palm-like nuts, called "petrified figs" (Org. Rem.vol. i. pl. vi. vii.Pict. Atlas, pl. vi. vii.) M. Ad. Brongniart has named several in hisProdrome; but without figures the descriptions are useless to the student. Mr. Bowerbank has published two numbers of a work entitled, "History of the Fossil Fruits of the London Clay," with seventeen plates; from which I have selected a few subjects for illustration. The fruits described are the following:

Lign. 63. Fossil Fruits from the Isle of Sheppey.London Clay.Fig.1. and 3.—Cucumites variabilis:fig.3, is a vertical section, showing the seeds.Lign. 64, fig. 6—1/2nat.2 and 8.—Petrophiloides Richardsoni:1/3nat.Fig. 8, is a vertical section, showing the disposition of the seeds in the cells formed by the confluent scales—1/2nat.4.—Wetherellia variabilis: a section of the fruit, in which state it is called coffee-berry by the collectors—1/3nat.5 and 6.—Faboidea semicurvilinearis: fig. 5, side view—1/4nat.6.—Is the face of a similar seed—1/3nat.7.—Faboidea bifalcis: side view—1/3nat.9.—Nipadites lanceolatus:a, the seed;b, the shell, or pericarp—1/2nat.10.—Nipadites cordiformis:a, the extremity of the seed, imbedded in the shell—1/3nat.

Lign. 64. Fossil Fruits from the Isle of Sheppey.London Clay.Fig.1 and 2.—Zulinosprionites latus. 2. A section, showing the receptacles for two seeds.—2/3nat.3.—Leguminosites dimidiatus; side view.—1/2nat.4.—Leguminosites subquadrangularis; side view.—1/2nat.5.—Cupanoides lobatus.—1/2nat.6.—Cucumites variabilis.—1/2nat.7.—Mimosites Browniana; from Ossington, Suffolk. A seed-pod of anAcacia, or other plant of theMimosafamily.—2/3nat.

Nipadites.Lign. 63. (Pict. Atlas, pl. vi. vii.)—The most remarkable fruits in the above catalogue are those which, from their appearance when compressed, are known to collectors by the name of "petrified figs" (Lign.63,fig.9, 10). Some specimens attain a considerable size, and are from five to seven inches long. The nut, and the pericarp or shell, are often well preserved. These fossils were referred to theCocosby Mr. Parkinson, but they have not a ligneous endocarp with three pores as in the Cocoa-nut.

Mr. Bowerbank has shown that they are nearly related to the fruit of theNipa, or Molucca-Palm, a tree which abounds in Bengal, and in the Molucca and Philippine Islands. The Nipæ are low, shrub-like plants, having the general aspect of palms; they grow in marshy tracts, at the mouths of great rivers, particularly where the waters are brackish. They are allied to the Cocoa-nut tribe, on the one hand, and to thePandanus, or Screw-pine, on the other.

TheNipadites, according to Mr. Bowerbank, have the epicarp and endocarp thin and membranous, and the sarcocarp thick and pulpy, and composed of cellular tissue, through which run numerous bundles of vessels. Nearly in the centre of the pericarp is situated a large seed which, when broken, is more or less hollow. This seed consists of regular layers of cells, radiating from a spot situated near the middle, and apparently inclosing a central embryo.

The same author remarks, that "if the habits of the plants to which the fossil fruits belonged were similar to those of the recentNipa, it will account for their abundance in the London Clay in the Isle of Sheppey; which formation, from the great variety of stems and branches, mixed up with star-fishes, shells of mollusks, and bones of fishes, crustaceans, and reptiles of numerous marine and fresh-water genera, is strikingly characteristic of the delta of a river, which probably flowed from near the Equator towards the spot where these interesting relics are deposited." The fact that theseed-vessels of several species of Nipadites abound in the Isle of Sheppey, and have not been observed in any other locality in England, tends to support this opinion.

Carpolithes of this kind occur in great perfection in the Eocene strata of Belgium, and were figured and described, nearly seventy years since, in Burton's "Oryctographie de Bruxelles," as petrified cocoa-nuts; the uncompressed state in which these fossils occur makes the resemblance to the recent fruit more striking than in the flattened pyritous specimens from the clay of Sheppey.

NIPADITES OF BELGIUM.

TheNipaditesof Brussels have recently been brought under the more immediate notice of English geologists, in a memoir "On the Tertiary Strata of Belgium and French Flanders," by Sir Charles Lyell, in which several specimens are figured and described.[165]These fossils are found in sands and sandstone, presumed to be of the age of the Bracklesham beds of Sussex. They are procured from Schaerbeek, in the northern suburbs of Brussels, where extensive quarries are worked for paving-stones, and have long been celebrated for remains of turtles, trunks of palms, and dicotyledonous trees, and the fruits, now called Nipadites. The vegetable remains often occur silicified; Sir C. Lyell was shown by the workmen "the trunk of a petrified exogenous tree, with forty rings of annual growth; it had lain in a horizontal position, and was bored by teredinæ. The silicified base of the trunk of a Palm-tree, apparently broken off short at about the level of the soil, had numerous air-roots, or rootlets, attached."[166]

[165]Quarterly Journal of the Geological Society of London, vol. viii. August 1852.[166]"On the Belgian Tertiary Formations," Geol. Journal, vol. viii, p. 344.

[165]Quarterly Journal of the Geological Society of London, vol. viii. August 1852.

[166]"On the Belgian Tertiary Formations," Geol. Journal, vol. viii, p. 344.

Of the thirteen species of Nipadites enumerated by Mr. Bowerbank, some of which are, however, only accidental varieties, four have been identified among those obtained from Schaerbeek: two of them belong to but one species—theNipadites Burtoni: the others areN. lanceolata(Lign. 63, fig. 9), andN. Parkinsoni(Pictorial Atlas, plate vii.). These fossil nuts closely resemble the fruit ofNipas fruticans, a palm which abounds in the delta of the Ganges, and other parts of Bengal, and is the only living species of the genus known.[167]In an immature or abortive specimen ofNipadites giganteus(of Bowerbank), figured inGeol. Journ.pl. xix. fig. 2, the angularity of the pericarp observable in the ripe fruit (Lign. 63. fig. 9) is well marked. The largest specimen of Nipadites from Schaerbeek, is above seven inches long and four wide. The arenaceous strata containing these fruits, and stems of palms and dicotyledonous trees, are supposed to have been formed in the sea near the mouth of a river, as in the case of the clay-beds at Sheppey: the vegetable remains are associated with bones of fresh-water Turtles, teeth of Sharks, cases and spines of Echinoderms, and shells of the genera Ostrea, Pinna, &c.[168]

[167]"On the Belgian Tertiary Formations," Geol. Journal, vol. viii. p. 344.[168]Geol. Journal, vol. viii. p. 347.

[167]"On the Belgian Tertiary Formations," Geol. Journal, vol. viii. p. 344.

[168]Geol. Journal, vol. viii. p. 347.

FOSSIL PANDANUS.

Fossil Fruit of Pandanus.(Popocarya.Bd.pl. lxii. p. 503.)—ThePandanaceæare monocotyledonous trees, named Screw Pines from the spiral insertion of their long, rigid, sword-like leaves, along the stem; they are natives of hot climates, and abound in the groups of islands in the Pacific; being generally the first important vegetable tenants of the newly-formed Atols or coral-islands. As in the palms, the stem is supported near the base by long side-roots, which enable these trees to maintain an erect position, and flourish on the newly-elevated coral-reefs, where but little soil has accumulated.

The existence of this tribe of plants during the secondary ages is known only by a single example of a fossil fruit,which was discovered by Mr. Page, of Bishport, in the Inferior Oolite, to the east of Charmouth, Dorsetshire, and is preserved in the museum at Oxford; no vestiges of the stems or foliage have been observed.

Lign. 65. Fossil Wood with Teredines;nat.London Clay, Regent's Park.Fig.1.—A polished transverse section, showing the tubes lined with spar.2.—Portions of mineralized Teredines, seen in relief on the wood.

This carpolithe, (for a detailed account and figures seeBd.p. 504, pl. lxiii.) is of the size of a large orange; the surface is covered with a stellated epicarpium, composed of hexagonal tubercles forming the summits of cells which occupy the entire circumference of the fruit. Each cell contains a single seed, usually hexagonal, resembling a small grain of rice, and is supported by a foot-stalk, formed of dense fibres; a character exhibited only by the seed-vessels of Pandanus. The fossil fruit differs from that of the recent Screw-pines in the seeds being neither inclosed in a hard nut, nor collected into drupes, but dispersed uniformly over the entire mass; this forms the essential generic distinction between them. Dr. Buckland has named this unique carpolithePodocarya. (Bd.p. 505.)

Wood perforated by Teredinæ.Lign. 65.—The drifted trunks and masses of wood found in the London Clay, at Sheppey, Bognor, Bracklesham, &c., some of which belong to Palms, others to Conifers, and Dicotyledons, are commonly more or less perforated by the boring mollusks calledTeredo, orTeredina; and remains of their testaceous tubes are often well preserved. The tortuous channels excavated in the wood by these borers, are lined or filled up with calcareous spar, indurated clay, or other mineral matter, of various shades of grey, blue, yellow, &c.; and the polished slabs of this fossil wood are beautifully diversified by the sections of the sparry tubes, crossed at right angles by the ligneous structure; as in the specimenfig. 1, Lign. 65, from the Canal in the Regent's Park.[169]

[169]Slabs of this kind are generally kept by the lapidaries at Bognor, Worthing, &c. and sold at 2s.or 2s.6d.each.

In the fossil,fig. 2. Lign. 65, from the Isle of Sheppey, the tubes of the teredinæ are seen in relief, in consequence of the surface of the block of wood having decayed and been removed.

Fossil Liliaceæ.—The family of endogens, termedLiliaceæ, comprises many beautiful plants; those with annual stems, as the Lily, Hyacinth, Tulip, &c. are well known for the variety and splendour of their blossoms; some of the arborescent forms, as the Tulip-tree, attain a large size, but the flowers of this division are relatively small. In tertiary strata, the stems, leaves, fruits, and even the imprints of flowers, have been discovered, of plants related toSagittaria(Arrow-head),Smilax(Bind-weed),Convallaria(Lily of the valley), &c.

The Dracæna (Dragon-blood tree), a tall, slender, elegant tree with amplexicaul leaves (common in our hot-houses), belongs to this family; and certain stems found with Clathrariæ, and bones of the Iguanodon, in the Kentish-rag at Maidstone (ante,p. 173.), so closely resemble the trunk of this plant, that they have been named by Mr. König,[170]Dracæna Benstedi; the specimens are in the British Museum. Until the internal structure of these fossils has been examined, the correctness of this identification is, however,uncertain: the external resemblance to the stem of the Dracæna consists in the interrupted annular ridges, denoting amplexicaul leaves: no vestiges of the foliage have been observed.

[170]Petrifactions, p. 49.

FRESH-WATER PLANTS. FOSSIL CHARÆ.

Fossil Fresh-water Plants.—The tertiary fresh-water strata often contain abundance of the remains of the aquatic vegetables that inhabited the lakes and rivers in which those deposits were formed. The remains of several species of the common lacustrine plant, theChara, are found in immense quantities in the fresh-water limestones and marls of the Isle of Wight, of the coast of Hampshire, and of the Paris Basin. The shell-marls, still in progress of formation in the lakes of Scotland, and the travertine precipitated from thermal springs, in like manner envelop and preserve the leaves and fruits of recent species.

Fossil Fruits of Chara.(Gyrogonites.)Lign.66.—The Chara is a well-known inhabitant of almost every stream and rivulet. The stems are hollow, and composed of tubes filled with a fluid in which green globules circulate; they form beautiful microscopic objects for exhibiting the circulation in vegetables. The fruit consists of very small nuclei, contained in a calcareous pericarp, composed of five spirally twisted plates, that unite at the summit. These seed-vessels, when first discovered in a fossil state, were supposed to be the shells of mollusks, and a genus was formed for their reception with the name ofGyrogonites(twisted-stones); a term still employed, though the vegetable nature of these bodies is well known. InPlate III. fig. 5, a branch of the common Chara with seeds is represented: and figures of the seed-vessels, of two fossil species are given inLign. 66, figs. 1, 2.

Specimens of the fossil fruits and stems of Charæ, may be collected in abundance in the fresh-water limestone at East Cliff Bay, Isle of Wight.[171]

[171]See my Geology of the Isle of Wight,Lign. 5, p. 109.

Lign. 66. Fossil Fresh-water Plants.Eocene, Paris.Fig.1.—Seed-vessel ofChara helicteres× 10; side view.1a.—View of the base of the same.1b.—One of the spiral valves separated.1c.—View from above.2.—Seed-vessel ofChara medicaginula× 10. The upper figure is a side view: the lower, a view of the base.3.—Carpolithes ovulum, magnified side view.3a.—The same, natural size.3b.—Magnified view of the base of the same.4.—A piece of fresh-water limestone, with impressions of two stems ofNymphea arethusa×.

ThePurbeck bedsat Durlstone Bay, near Swanage, also contain numerous Gyrogonites associated with fresh-water shells. The bands of siliceous sinter, which occur in the lowermost deposits, are especially rich in these remains.[172]

[172]I am indebted to the Rev. Osmond Fisher, of Dorchester, for a fine suite of these and other interesting fossils from the Purbeck beds of Ridgway and Osmington, near Weymouth; and to William Shipp, Esq., of Blandford, and Edward Woodhouse, Esq., of Ansty, for many specimens from Durlstone Bay, and Ridgway.

Fossil Nympheæ.Lign. 66, fig. 4.—Those magnificent aquatic plants, the Water-Lilies (Nympheæ), that adorn our rivers and lakes with flowers and foliage which partake more of the characters of an exotic flora than any other of our indigenous plants, are also found fossil in the lacustrine marls and limestones of the tertiary formations of France; but the nature of these remains could only be recognized by a profound botanist, for they consist of impressions of the internal structure of the stems, which, however, is so peculiar, that no reasonable doubt of their origin can be entertained. Two imprints on a piece of limestone from Lonjumeau, presented to me by the late M. Alex. Brongniart, are figured inLign. 66, fig. 4; some minute seed-vessels (Lign. 66, fig. 3), found with them, closely resemble those ofNympheæ, and are supposed to belong to the same plants (Class. Vég. Foss.p. 72).

Fossil Flowers.—The tertiary limestones of Monte Bolca (Wond.p. 565), so rich in ichthyolites, and other fossil remains of great interest, contain leaves, and even flowers, of liliaceous plants. The specimen figured (Lign. 67, fig. 3) is in the Museum at Paris, and described by M. Brongniart under the name ofAntholithes(stone-flower)liliaceus; it consists of the corolla and calyx: the anthers and pistils have not been observed in any example. The discovery of this fossil should excite the young collector to search diligently for such objects in the tertiary strata of England.

FOSSIL ANGIOSPERMS.

Fossil Angiosperms.—The fossil remains of the class which constitutes the grand features of the existing floras of most countries, theExogenous Angiosperms, are now to be considered; and though our survey of fossil botany has partaken but little of a geological arrangement, yet the reader may have observed, that a large proportion of the vegetables composing the floras of the ancient secondary formations, belonged to the Cryptogamous and Gymnospermous classes. A striking contrast is presented in the geologicalposition of the mineralized dicotyledonous plants, of existing genera. These abound in the tertiary strata, and generally in an inverse ratio to the antiquity of the deposit, while their remains are almost wholly absent in the older rocks; neither have there been discovered in the Tertiary, any beds of vascular cryptogamia, at all approaching the immense accumulations in the Carboniferous formations.

Lign. 67. Fossil Nuts, and Flower.Fig.1.—Thalictroides Parisensis; Tertiary strata, Paris.2.—Thalictroides Websteri.Isle of Wight.3.—Antholithes liliaceus.Monte Bolca.4.—Juglans nux-taurinensis: fossil Walnut, Turin.4a.—-Portion of the husk of the shell.4b.—The kernel, formed of calcareous spar.

The most remarkable exception, is the single instance of a large leaf of a dicotyledonous plant in the Trias, or New Red sandstone, near Liverpool, described by Sir Roderick Murchison, which much resembles the foliage of a thick-ribbed Cabbage.[173]

[173]This fossil is namedDictyophyllum crassinervium, by Dr. Lindley, Foss. Flor. pl. cci. and is figured, Sil. Syst. p. 43.

It would be impossible, within the limits necessarily assigned to these volumes, to offer even a general view of the fossil remains of this grand class of vegetables; our remarks must be limited to a few interesting examples and localities.

When stems of dicotyledonous trees only are found, but little certainty can be obtained as to the family to which they belonged; the foliage of many well-known genera offer more positive characters; the flowers are rarely in a state of preservation to afford any valuable data; but the fruits, or seed-vessels, are frequently well preserved, and these may enable the botanist to arrive at precise determinations as to generic, and, perhaps, specific relations.

The tertiary marls of Aix, in Provence, which abound in insects, crustaceans, and lacustrine shells, contain many kinds of dicotyledonous leaves, associated with those of palms. (Wond.p. 260.)

The Lignite, or Brown-coal deposits, are almost entirely composed of dicotyledonous trees, belonging to many genera, which are inhabitants of Europe; namely, the Poplar, Willow, Elm, Chestnut, Walnut, Sycamore, Maple, Linden, Buckthorn, Vine, &c. (Bd.vol. i. pp. 508-514.)

The beds of brown coal, on the banks of the Rhine, are literally carbonized submerged forests, which in some remote period were drifted from the interior of the Continent into a vast lake or gulf; for the trees bear evident marks of transport, and are destitute of roots and branches. These masses resemble the rafts of forest trees, which are daily floated down the Mississippi into the Atlantic, where they become engulfed in the profound depths of the ocean, and probably will be converted into coal or lignite; and in future ages, may be elevated above the waters, become dry land, and present to the then existing communities of mankind an inexhaustible supply of mineral fuel, composed of species and genera of plants, which possibly maythen be extinct, and replaced by peculiar types of vegetation.

Fossil Flora of Œningen.(Bd.pp. 511-514).—The celebrated lacustrine tertiary formation of Œningen, whose fossil reptiles and mammalia we shall have to notice hereafter, contains a rich assemblage of dicotyledonous and gymnospermous ligneous vegetables, with a few ferns and grasses. Not only branches and leaves of a species of Vine[174]occur, but even the fruit; fossil grapes being found in these deposits;[175]there are also many aquatic plants. A descriptive list of these fossils, by Professor Braun, of Carlsruhe, is given by Dr. Buckland. The brown-coal of this basin is in thin beds of but little economical importance, but so rich in the vegetation of the miocene tertiary period, that a few days spent in collecting those treasures will amply reward the intelligent tourist who may visit Constance. (SeeWond.p. 263.)

[174]See Knorr, Mon. des Catastrophes, pl. xxxviii. tom. i.[175]Fossil grapes from the lignite of Œningen were exhibited by Dr. Daubeny at a late meeting of the Geological Society.

[174]See Knorr, Mon. des Catastrophes, pl. xxxviii. tom. i.

[175]Fossil grapes from the lignite of Œningen were exhibited by Dr. Daubeny at a late meeting of the Geological Society.

FOSSIL DICOTYLEDONOUS LEAVES.

The foliage of dicotyledonous trees frequently occurs in the Eocene marls and limestones, and in some localities in considerable abundance, and in beautiful preservation. Near Bournemouth, on the Hampshire coast, the leaves of many species are met with in a bed of sandy marl, between three and four feet thick: the vegetable substance is carbonized; some of the leaves are referable to theLauraceæandAmentaceæ, others to theCharaceæ;[176]a similar deposit of tertiary plants has been discovered near Wareham. These beds belong to the lower group of the Hampshire Basin.[177]

[176]Geol. Proc. vol. iii. p. 592.[177]As the seed-vessels and other vegetable remains in the Isle of Sheppey are all of a tropical character, while those found in the Eocene strata of Alum Bay, Bournemouth, and Newhaven, are of a temperate climate, as Nerium, Platanus, &c., Prof. E. Forbes infers that the former were transported from distant lands by currents, and that the latter belong to the true flora of the country inhabited by the Palæotheria and other associated mammalia.

[176]Geol. Proc. vol. iii. p. 592.

[177]As the seed-vessels and other vegetable remains in the Isle of Sheppey are all of a tropical character, while those found in the Eocene strata of Alum Bay, Bournemouth, and Newhaven, are of a temperate climate, as Nerium, Platanus, &c., Prof. E. Forbes infers that the former were transported from distant lands by currents, and that the latter belong to the true flora of the country inhabited by the Palæotheria and other associated mammalia.

Lign. 68. Imprints of Dicotyledonous Leaves in Gypseous Marl.Tertiary. Stradella, near Pavia.Fig.1.—Leaf of Poplar (Populus græca).2.————– Maple (Acer).3.————– Water-spike (Potamogeton).4.————– Willow (Salix).5.————– Chestnut (Æsculvs).

The red marlstone associated with lignite in the plastic clay beds at Castle Hill, Newhaven (Geol. S. E.p. 54), contains leaves of a similar kind; a seed-vessel of a coniferous tree has also been found in it.

Some of the most interesting examples of dicotyledonous leaves that have come under my notice, are from the Sub-Apennine tertiary strata, at Stradella, near Pavia. They belong to several genera of arborescent, or at least ligneousplants, and most of them to species which still grow in Italy. In some examples the substance of the leaves is changed into carbon, and the structure well preserved; but, in general, sharp imprints on the stone are the only traces of the originals. They are found in a gypseous marl, of a cream colour; and, from their perfect state, it is inferred that they were enveloped in the soft matrix immediately after their fall, and preserved by the rapid crystallization of the gypsum. Two specimens from my cabinet are figured inPlate III.figs.4 and 8; and outlines of a few other examples, inLign. 68.

Carpolithes(Fossil Fruits).—In the description of the fossil fruits from the Isle of Sheppey, several kinds of dicotyledons were included. Many species also abound in the lignites of Germany, France, and Italy; in those near Frankfort, seed-vessels of the Maple, Elm, Hornbeam, Birch, Willow, and Walnut, &c. In the environs of Turin, fruits of a species of Walnut (Juglans,Lign. 67), occur in the newer tertiary deposits, and are called Turin-nuts; the ligneous envelope has perished, but the form of its surface, and of the inclosed kernel, is preserved in calcareous spar. These nuts differ, both in the pericarp and kernel, from the living species: the lobes are simple (Lign. 67, fig. 4b), and not subdivided as in the common walnut; a species has been discovered at Lons-le-Saulnier, in which the lobes are mamillated.

Two kinds of fruits belonging to plants of the orderRanunculaceæ, and related toThalictrum(Meadow-rue), have been found in the eocene deposits of France and England; one in the Paris basin, (meulière du terrain d'eau douce supérieur,) by M. Alexandre Brongniart, and the other in the Isle of Wight, by Mr. Webster. In the specimen from the last-named locality the pericarp is carbonized, and its cavity filled with clay. Figures of these seed-vessels are given inLign.67,figs.1, 2.

Carpolithes Smithiæ.—I would notice in this place somevery remarkable fossil fruits that are occasionally met with in the White Chalk of Sussex and Kent, and appear to belong to dicotyledonous trees. The first specimen was discovered by me in a chalk-pit near Lewes, and is described in my "Fossils of the South Downs:" some illustrative examples collected by Mrs Smith, of Tunbridge Wells, tending to elucidate the nature of the original more satisfactorily than those in my collection, are figured and described by me in the Journal of the Geological Society, 1843, under the above name. These fruits are of an oval form, about one and a half inch long, and one inch wide, and are pressed almost flat. They are of a rich burnt-sienna colour, mottled with white, from the chalk having permeated their substance, and are studded over with slight eminences, which are the exposed summits of oblong flattened seeds. Although the internal structure is not preserved, there can be no doubt that the originals were spurious compound berries, having, like the Mulberry, the seeds imbedded in a soft pulpy mass.

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