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lished, of small silicified stems, from Chemnitz in Saxony (I believe, from the carboniferous deposits), the internal structure of which is peculiar. The vascular tissue resembles that of Dracena, but with essential differences, which render it difficult to establish any relation with existing types. M. Brongniart is of opinion that they will be found to belong to the Cycadeaceæ.

FOSSIL PALMS.-Cases D, E. [5. c.D.] The trees of this family, the greater number of which inhabit intertropical regions, are remarkable for their elegant form and peculiar aspect. They have a single cylindrical stem, which rises to a great height, and is crowned with a canopy of foliage, the leaves being very large, and either pinnated or flabelliform, and plaited in regular folds. The Date and Cocoa-nut are well-known examples of the fruit. The surface of the stem is scored with transverse scars left by the petioles.

In a fossil state, the remains of this family are very abundant; the stems with their external characters and internal organization preserved, and the leaves and the fruit, of several extinct species, have been discovered; chiefly in tertiary deposits.1 From the manner in which the specimens are arranged in the collection, it will be convenient to notice in the first place the fossil Palm-nuts in the case before us.

FRUITS OF PALMS, from the Isle of Sheppey.-Case E.-On the right hand of the central compartment in this case, there is a very small collection of fossil fruits, from the well-known productive locality of this class of organic remains, the Isle of Sheppey; and it is much to be regretted that our National Museum is so deficient in these most interesting relics of this ancient tertiary flora; especially when from the unrivalled and inexhaustible mine of these botanical treasures in the little Island at the mouth of the Thames, there might be obtained in the course of a few months, and at a trifling cost, a more extensive and important series of the fruits of the Eocene periods, than is contained in all the museums of Europe.

Referring the reader to "Medals of Creation," pp. 176, 897, for a particular account of these fruits, and the cir

1 See "Medals of Creation," p. 173.

cumstances under which they occur, I proceed to notice the only specimens worthy of remark. These are two or three examples of the nuts of an extinct genus of palm, closely allied to the recent Nipa, which is a low shrub-like plant that inhabits the Moluccas, growing in marshy tracts near the mouths of rivers, where the water is brackish. The Nipa has borne fruit in the conservatory of Mr. Yates, of Lauderdale House, Highgate. The fossil fruits (named Nipatites Parkinsoni), are known to the resident dealers and collectors at Sheppey as "petrified figs." The nut or seed, and its pericarp or husk, are often well preserved, as in one of the specimens in the case before us.' Mr. Bowerbank, who some years since assiduously collected the fossil fruits of the Isle of Sheppey, and published three numbers of a work on the subject, whose excellence renders its discontinuance much to be regretted, has figured and described several species. Mr. B. observes, that "if the habits of the plants to which the fossil fruits belonged were similar to those of their recent analogue, the Nipa, it will account for their abundance in the London clay in the Isle of Sheppey; which formation, from the great variety of the fossilized 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 characterized as having been the delta of an immense river, which probably flowed from near the equator towards the spot where these interesting relics are deposited."3

Palmacites Lamanonis.-Case E. [5,]-In the narrow recess in this case, on the left of the door-way, there is a palm-leaf imbedded in cream-coloured limestone, from the Eocene deposits of Aix, in Provence (this specimen was formerly in the Author's collection). The leaves of several extinct species of

1 Figured in "Pictorial Atlas," Pl. VI. VII.

2 66

History of the Fossil Fruits and Seeds of the London Clay of the Isle of Sheppey." 1840: London.

3 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 should be regarded as transported from distant lands by currents, and the latter as the true flora of the country inhabited by the Palæotheria and other associated mammalia.

palms have been collected from the tertiary strata of various parts of the Continent, but the first example discovered in England was obtained a few months since, from the freshwater tertiary deposits at White-Cliff Bay, in the Isle of Wight, by Mr. Fowlstone, of Ryde.'

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LIGN. 17.-PALM-LEAF FROM EOCENE STRATA. ISLE OF WIGHT.
Palmacites Lamanonis. (nat. size.)

Palm-stems.-Cases D. and E.-The lower shelves of Case E, beneath the fossil fruits from Sheppey, contain many specimens of silicified stems of palms; and on the top of Case D, there are several very large petrified trunks from Antigua, and from the Eocene deposits of India. Some of these fossils retain vestiges of the air roots which proceed from the lower part

1 See "Geological Excursions round the Isle of Wight," &c., 2d edit. 1851, p. 431.

of the stem in this tribe of vegetables. The internal structure is in most instances exquisitely preserved, and sections under the microscope exhibit the organization of the original as distinctly as in the recent state. Some of these fossils are very beautiful objects under a slightly magnifying power, whether viewed by reflected or transmitted light, owing to the rich tints of crimson, yellow, brown, &c. of the silex into which the vascular tissue is transmuted.1

CONIFERE.—Case F. [6. A.D.E.]—The trees and plants that are comprised under the term Coniferæ, or cone-bearing, from the form of their fruit, constitute an extensive and most important tribe, which is divided into two families: the Coniferæ, strictly so called, as the Pine, Fir, Larch, Cypress, &c.; and the Cycadea, of which the Cycas and Zamia of our conservatories are familiar examples. These families are distinguished from all other dicotyledons by the remarkable peculiarity of the seeds being originally naked or exposed, and not enclosed within an ovary; hence the botanical name of the order-Gymnospermous Phanerogamia.

The conifers are all arborescent, dividing into numerous branches, which are disposed with considerable regularity; many are among the loftiest trees on our globe. The leaves are in most species acicular, or needle-shaped, narrow and linear; in two or three, however, they are broad and flat. The structure of the wood, though dicotyledonous, is so peculiar, that it may be readily detected in a fossil state. There are no true vessels, and the ligneous fibres are disposed in series which extend parallel with the medullary rays, having on the corresponding surfaces, or laterally, rows of regular punctuations or ducts, with a central pore surrounded by a discoidal areola. These ducts or glands, when in double rows, are placed side by side in the European pines and firs; but in the Araucaria (Norfolk Island pine) they are arranged alternately; and such is generally the case in the fossil coniferous wood of the secondary and paleozoic formations of England. Vestiges of the coniferæ occur in the various deposits from the earliest

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1 A specimen, as seen by reflected light, is figured in Medals of Creation," Pl. V., fig. 1.

2 See "Medals of Creation," Pl. V. p. 162; and "Wonders of Geology," 6th edit. pp. 696, 724.

The

traces of terrestrial vegetation to the present time.' trunks and branches, leaves, and the fruits or cones, of numerous trees of this family abound in a fossil state, and in the Case before us, there are many interesting specimens which our limits will not permit us to dwell upon. There are fruits

of pines and firs from the Crag deposits, and from the greensand of Kent; and foliage and stems of pines, araucariæ, thuytes, &c., from the Lias and Oolite.

Voltzia. The Case Falso contains some fine specimens of Voltzia, a genus peculiar to the Triassic deposits, and one of the most characteristic of the extinct fossil coniferæ. The leaves of these plants are alternate, and have much analogy in their form and arrangement with the foliage of the Araucariæ. The fruits are oblong cones, with scales slightly imbricated, which do not appear to have been contiguous, are cuneiform, and generally have from three to five obtuse lobes: the disposition of the seeds or grains is not determined.2 Fossil Cycadeous Plants.-The Zamia and Cycadeæ are plants with cylindrical stems, beset with thick scales, which are the bases of petioles that have been shed: the summit of the stem is crowned with elegant pinnated leaves with simple veins, and which in the young state are coiled up like a crosier, as in the ferns. The Zamiæ are generally short and robust plants, but the Cycadeæ are longer, and some species are bifurcated, and attain a height of from twenty to thirty feet. The fruits bear a general resemblance to the cones of the pines, but the seeds are naked. The Cycadeæ are natives of hot and humid climates, and inhabit the West Indies, Cape of Good Hope, the Molucca Islands, Australia, &c.

Numerous extinct species and genera of this family occur in a fossil state, and they are especially abundant in the secondary deposits-the Lias and Oolite. In England the most fruitful locality is the Yorkshire coast, near Scarborough, where, in the intercalated fluvio-marine clays and shales of the Oolite, leaves and fruits of numerous species are found in great variety and perfection. The foliage is changed into

'The association of coniferæ with palms and arborescent ferns in the coal-measures, continues through all the subsequent formations to the tertiary.

2 Two species of Voltzia are figured in "Wonders of Geology," p. 547.

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