ORIGIN AND DISTRIBUTION OF MAMMALS 301 



more numerous are the elements foreign to the European fauna, especially 

 among the ruminants. While in Europe the antelopes play a comp»aratively 

 small part, and the deer consequently are better represented, the latter disap- 

 pear almost completely in the east, and the antelopes assume a correspondingly 

 rich development. In Central Europe the Lower Pliocene fauna, apart from 

 the presence of Hipparion instead of the extinct genus Anchitheriurn, is only a 

 continuation of the Upper Miocene mammal world, for the carnivores, the 

 perissodactyls — Brachi/jwiherium, Aceratherium, Tapirus, Chalicotherium — the 

 proboscideans — Mastodon, Tetrabelodon, and Dinotherium — are only little altered 

 descendants of the Upper Miocene species. The same is true of the artio- 

 dactyls — pigs, deer, Dorcatherium, and the few antelopes ; while even the apes, 

 Dri/opithecus and Anthropodus, may have been derived from Pliopithecus. The 

 rodent faana is extremely poor, because almost all the deposits of this period 

 were formed either by great floods or by gravel-bearing rivers, and most small 

 bones were destroyed : it consists chiefly of Castor, Lepus and Bipoides. The 

 two latter genera . came from the east, through Asia from North America, 

 evidently at the same time as some Felidae and Hipparion. Hyaena is also an 

 immigrant from the east. These few new faunal elements of western Europe 

 are in sharp contrast to the multitude of new types which Ave meet with in 

 South-eastern Europe and Western Asia. The Lower Pliocene fauna of Pikermi 

 comprises a rhinoceros, Atelodus pachygnathus, different from .the European 

 forms ; while on Samos and in Maragha there are further aceratheres resem- 

 bling Chinese and Indian types. Quite unexpectedly there also appears here a 

 large hyracoid, Pliohyrax. Specially characteristic also are the giraffes, Camel- 

 opardalis, Helladotherium, Samotherium, Palaeotragus, etc., which are absent 

 entirely from the west. Further, there are Palaeoryx, Protoryx, ProtragelapJms, 

 and other antelopes ; while in central and western Europe such are restricted 

 to Palaeoreas, Tragocerus and Gazella. The hyaenas, as well as Iditherium and 

 Mesopithecus, are also decidedly eastern types. The fauna of Samos and 

 Maragha leads us naturally to refer to the fauna of the Siwalik Hills, India, 

 and of China. In the Siwalik, the greater part of the fossil mammalian 

 remains belong indeed to the Lower Pliocene ; but there is also an older fauna 

 of European origin at least characterised by Anthracotheriwn, Merycopotamus, 

 and a primitive species of Hemimastodon. Dinotherium and Listriodon perhaps 

 also belong to this older fauna. The Pliocene fauna is distinguished by the 

 occurrence of several primates — Palaeopithecus, Sivapithecus, Simia, Macacus and 

 Cynocephalus. The beasts of prey are represented by Canis, Amphicyon, Hyaen- 

 ardos, Ursus, Mellivora, Enhydriodon, Viverra, Machaerodics, and comparatively 

 numerous species of Hyaena and Felis. The genus Mastodon is likewise rather 

 rich in species, and among the rhinoceroses there occur with European types 

 some new forms which are of importance in the ancestry of existing species 

 and also of Bhinoceros antiquitatis (or tichorhinus). With Hipparion there also 

 appear here, as in China, species of Equus. The numerous Suidae have already 

 a very modern aspect. With many deer we find giraffes, and the strange 

 Sivatheriinae and numerous antelopes, which in part, as Strepsiceros, Hippotragus 

 and Alcelaplms, live at present in Africa, like the genus Hippopotamus, which 

 appears for the first time in the Siwalik fauna. No less important is the 

 occurrence of Camelus, Capra, Buhalus and other Bovidae, although these 

 perhaps belong to the younger Stegodon-i&yxn?^, which was so widely spread 

 throughout Southern Asia. The mammalian remains in the red clays and 



