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fauna of the oldest tertiary seas was totally disconnected from that of the cretaceous epoch.
The first tertiary land concerning which we have distinct knowledge was richly clothed by a vegetation, a good deal of whose general character is recognised by examining the fruits of trees and fragments of wood found abundantly in the Isle of Sheppey. These fossils are exceedingly numerous and varied, and the fruits obtained from the single locality just alluded to include several hundred species, all of which are different from existing and known plants, although many of them seem closely allied to generic forms now met with in warmer climates than those at present characterising similar latitudes. A portion of one of these fruits is figured in the annexed cut; it marks the existence of a five-seeded fruit which was enveloped in a mass of downy filamentous structure. The plant was probably allied to the natural order of Malvacea. There is, indeed, nothing in these plants which removes them at once and in a marked manner from the existing type; and the most remarkable fact concerning them as a group is the preponderance of species allied to the palms, some of them being apparently intermediate between the cocoa-nut and the Pandanus, or screw-pine wellknown and common tropical plants,
* So called from the name of a botanist, J. Hight, Esq.
A very common fruit in Sheppey. It contains a single seed nearly
in the centre, closely resembling that of the cocoa-nut, and with a very hard shell.
not met with now in northern latitudes. The recent analogues of another genus, Nipadites (fig. 112), the family of Nipa, inhabit the Spice Islands and Japan, and chiefly in low damp or marshy tracts at the mouths of great rivers, especially in brackish water. Associated with these are some varieties of the cucumber, or gourd tribe, the pod of a variety of Acacia or Mimosa (see fig. 113), the seeds of cypress-like plants, and the fruits of some coniferous trees. There are also fragments of wood and stems indicating the presence of a species of the pepper plant,-of several varieties of palm-trees, and of several coniferous trees. The wood has often been pierced and almost destroyed by an extinct species of teredo before it was deposited in the bed where it is now found; and sometimes it presents little else than a collection of the tubular cavities of these animals filled with carbonate of lime.
The older tertiaries of the London Basin, of the Hampshire and Isle of Wight Basins, of the Paris Basin, and of the neighbourhood of Brussels, are all contemporaneous deposits, and differ only in conse. quence of local peculiarities caused by the nature of the material. The oldest part of each, which is everywhere a coarse pebbly bed, may possibly have once been spread pretty uniformly over the whole tract;
but, afterwards, when the land had risen above the sea in various places, and yielded different kinds of detritus, the water in some places was nearly fresh, in others brackish, and in others, again, perfectly salt. In this way all varieties of development are accounted for; and we may understand how the coarse and occasionally flinty limestone found at Paris, the great and uniform mass of clay near London, the marly clay of Brussels, the highly siliceous material, probably deposited from warm springs, in central France, and the limestones of the Greek Archipelago and Asia Minor, all present fossils having something of the same general character, and belonging to the same epoch. In the tertiary beds in western Europe, there is, on the whole, not much distinct uniformity of character; but when we examine the contemporaneous deposits of northern India and South America, we find evidence of the operations of nature having been conducted on as grand a scale during the tertiary as during the preceding geological epochs.
The beds of London clay at Sheppey and elsewhere are not only remarkable for the amount of information they give us concerning the vegetation of the early tertiary period in Europe, but are almost equally instructive with regard to the animal inhabitants of the land at that time.
A considerable number of shells are found, both univalve and bivalve, of which the annexed figures (114—117) will give some idea, but the most remarkable fact concerning them is the absence of the whole group of ammonites, and their replacement by a newly-introduced genus of carnivorous trachelipods (animals of lower organization), which here
abound in the most remarkable profusion. Upwards of two hundred species of these shells (Cerithium, fig. 116) are found in the older tertiary beds of Europe. The nautilus is retained in these beds,
especially in the London clay (the most distinct marine deposit), but it has ceased to be the represen
tative of the prevailing
group of mollusca. In addition to the shells there are in the beds at Sheppey a multitude of the remains of crabs and lobsters, some of them exceedingly perfect, indicating the vicinity of a coast-line at
the time when this part of the series was deposited. One of these is figured (118), to give an idea of the near resemblance of them to existing species. Figures are also given (119, 120) of a species of
Fig. 114, Lucina. Fig. 115, Corbula. Fig. 116, Cerithium. Fig. 117, Cone.
foraminiferous shell, called Nummulite (from nummulus, a little piece of money), whose remains are so incredibly abundant in some localities, that rocks are made up of them, and which, although belonging also to the secondary epoch, must be considered characteris
tic of some older tertiary beds. Other
ferous shells have
built great masses of the limestone of this period.† Besides the numerous shells and other invertebrate remains, the older beds of this newest epoch afford many very interesting fragments of fishes, of reptiles, of birds, and even of quadrupeds. In order to obtain a general view of the eocene fauna, we must consider some of these a little in detail.
The fishes naturally present themselves first for investigation and description, and their remains, as well in the London clay as at Monte Bolca in north Italy, and in a remarkable deposit, probably of the same age, in Asia Minor (Lebanon), are very numerous. They are not, however, in all cases very well preserved, and this is especially the case with regard to those found in the tenacious blue clay of the Thames valley, where there is frequently nothing to be obtained but a few bones of the head. It is thus far more difficult to determine their analogies than those of the older fishes, where we gene
*Fig. 119 shows the external surface of the shell, and fig. 120 the appearance of a section, the light parts being the chamber-walls, or septa. A great part of Paris is built with a limestone of this kind.