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can plants to Europe was thus permitted. This view is borne out by the fact that the Miocene plants of Europe are most nearly allied to the living plants of the eastern or Atlantic seaboard of the United States, and also by the occurrence of a rich Miocene flora in Greenland. As regards Greenland, Dr Heer has determined that the Miocene plants indicate a temperate climate in that country, with a mean annual temperature at least 30° warmer than it is at present.

The present limit of trees is the isothermal which gives the mean temperature of 50° Fahr. in July, or about the parallel of 67° N. latitude. In Miocene times, however, the Limes, Cypresses, and Plane-trees reach the 79th degree of latitude, and the Pines and Poplars must have ranged even further north than this.

The Invertebrate Animals of the Miocene period are very numerous, but they belong for the most part to existing types, and they can only receive scanty consideration here. The little shells of Foraminifera are extremely abundant in some beds, the genera being in many cases such as now flourish abundantly in our seas. The principal forms belong to the genera Textularia (fig. 237), Robulina, Glandulina, Polystomella, Amphistegina, &c.

Corals are very abundant, in many instances forming regular "reefs ;" but all the more important groups are in existence at the present day. The Red Coral (Corallium), so largely sought after as an ornamental material, appears for the first time in deposits of this age. Amongst the Echinoderms,

Fig. 237.-Textularia Meyeriana, greatly enlarged. Miocene Tertiary.

we meet with Heart - Urchins (Spatangus), Cake - Urchins (Scutella, fig. 238), and various other forms, the majority of which are closely allied to forms now in existence.

Numerous Crabs and Lobsters represent the Crustacea; but the most important of the Miocene Articulate Animals are the Insects. Of these, more than thirteen hundred species have been determined by Dr Heer from the Miocene strata of Switzerland alone. They include almost all the existing orders of insects, such as numerous and varied forms of ·Beetles (Coleoptera), Forest-bugs (Hemiptera), Ants (Hymenoptera), Flies (Diptera), Termites and Dragon-flies (Neuroptera), Grasshoppers (Orthoptera), and Butterflies (Lepidoptera).

One of the latter, the well-known Vanessa Pluto of the Brown Coals of Croatia, even exhibits the pattern of the wing, and to

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Fig. 238.-Different views of Scutella subrotunda, a Miocene "Cake-Urchin " from the south of France.

some extent its original coloration; whilst the more durablyconstructed insects are often in a state of exquisite preservation.

The Mollusca of the Miocene period are very numerous, but call for little special comment. Upon the whole, they are generically very similar to the Shell-fish of the present day; whilst, as before stated, from fifteen to thirty per cent of the species are identical with those now in existence. So far as the European area is concerned, the Molluscs indicate a decidedly hotter climate than the present one, though they have not such a distinctly tropical character as is the case with the Eocene shells. Thus we meet with many Cones, Volutes, Cowries, Olive-shells, Fig-shells, and the like, which are decidedly indicative of a high temperature of the sea. Polyzoans are abundant, and often attain considerable dimensions; whilst Brachiopods, on the other hand, are few in number. Bivalves and Univalves are extremely plentiful; and we meet here with the shells of Winged - Snails (Pteropods), belonging to such existing genera as Hyalea (fig. 239) and Cleodora. Lastly,

Fig. 239.-Different views of the shell of Hyalea Orbignyana, a Miocene Pteropod.

the Cephalopods are represented both by the chambered shells of Nautili and by the internal skeletons of Cuttlefishes (Spirulirostra.)

The Fishes of the Miocene period are very abundant, but of little special importance. Besides the remains of Bony Fishes, we meet in the marine deposits of this age with numerous pointed teeth belonging to different kinds of Sharks. Some of the genera of thesesuch as Carcharodon (fig. 241), Oxyrhina (fig. 240), Lamna, and Galeocerdo-are very widely distributed, ranging through

both the Old and New Worlds; and some of the species attain gigantic dimensions.

Amongst the Amphibians we meet with distinctly modern types, such as Frogs (Rana)

and Newts or Salamanders. The most celebrated of the latter is the famous Andrias Scheuchzeri (fig. 242), discovered in the year 1725 in the fresh-water Miocene deposits of Eningen, in Switzerland. The skeleton indicates an animal nearly five feet in length; and it was originally described by Scheuchzer, a Swiss physi

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cian, in a dissertation published in 1731, as the remains of one of the human beings who were in existence at the time of the Noachian Deluge. Hence he applied to it the name of Homo diluvii testis. In reality, however, as shown by Cuvier, we have here the skeleton of a huge Newt, very closely allied to the Giant Salamander (Menopoma maxima) of Java.

The remains of Reptiles are far from uncommon in the Miocene rocks, consisting principally of Chelonians and Crocodilians. The Land-tortoises (Testudinida) make their first appearance during this period. The most remarkable form of this group is the huge Colossochelys Atlas of the Upper Miocene deposits of the Siwâlik Hills in India, described by Dr Falconer and Sir Proby Cautley. Far exceeding any living Tortoise in its dimensions, this enormous animal is estimated as having had a length of about twenty feet, measured from the tip of the snout to the extremity of the tail, and to have stood upwards of seven feet high. All the details of its organisation, however, prove that it must have been "strictly a land animal, with herbivorous habits, and probably of the most inoffensive nature." The accomplished palæontologist just quoted, shows further that some of the traditions of the Hindoos would render it not improbable that this colossal Tortoise had survived into the earlier portion of the human period.

Of the Birds of the Miocene period it is sufficient to remark that though specifically distinct, they belong, so far as known, wholly to existing groups, and therefore present no points of special palæontolgical interest.

The Mammals of the Miocene are very numerous, and only

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Fig. 242.-Front portion of the skeleton of Andrias Scheuchzeri, a Giant Salamander from the Miocene Tertiary of Eningen, in Switzerland. Reduced in size.

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the more important forms can be here alluded to. Amongst the Marsupials, the Old World still continued to possess species of Opossum (Didephys), allied to the existing American forms. The Edentates (Sloths, Armadillos, and Ant-eaters), at the present day mainly South American, are represented by two large European forms. One of these is the large Macrotherium giganteum of the Upper Miocene of Gers in Southern France, which appears to have been in many respects allied to the existing Scaly Ant-eaters or Pangolins, at the same time that the disproportionately long fore-limbs would indicate that it possessed the climbing habits of the Sloths. The other is the still more gigantic Ancylotherium Pentelici of the Upper Miocene of Pikermé, which seems to have been as large as, or larger than, the Rhinoceros, and which must have been terrestrial in its habits. This conclusion is further borne out by the comparative equality of length which subsists between the fore and hind limbs, and is not affected by the curvature and crookedness of the claws, this latter feature being well marked in such existing terrestrial Edentates as the Great Ant-eater.

The aquatic Sirenians and Cetaceans are represented in Miocene times by various forms of no special importance. Amongst the former, the previously existing genus Halitherium continued to survive, and amongst the latter we meet with remains of Dolphins and of Whales of the "Zeuglodont" family. We may also note here the first appearance of true "Whalebone Whales," two species of which, resembling the living "Right Whale" of Arctic seas, and belonging to the same genus (Balana), have been detected in the Miocene beds of North America.

The great order of the Ungulates or Hoofed Quadrupeds is very largely developed in strata of Miocene age, various new types of this group making their appearance here for the first time, whilst some of the characteristic genera of the preceding period are still represented under new shapes. Amongst the Odd-toed or "Perissodactyle" Ungulates, we meet for the first time with representatives of the family Rhinocerida comprising only the existing Rhinoceroses. In India in the Upper Miocene beds of the Siwâlik Hills, and in North America, several species of Rhinoceros have been detected, agreeing with the existing forms in possessing three toes to each foot, and in having one or two solid fibrous "horns" carried upon the front of the head. On the other hand, the forms of this group which distinguish the Miocene deposits of Europe appear to have been for the most part hornless, and to have resembled the Tapirs in having three-toed hind-feet, but four-toed fore-feet.

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