ORIGIN AND DISTRIBUTION OF MAMMALS 297 



among bunoselenodonts Anthracotherium and Ancodus ; and among bunodonts 

 Elotherkim, the Leptochoeridae and a true pig — Perchoerus. 



In Europe the Oligocene is characterised by the preponderating occurrence 

 of the genus Anthracotherium and the presence of numerous primitive Acera- 

 thermm-\ike rhinoceroses. A rather rich fauna restricted to a short period of 

 time is known from lionzon, Haute Loire. The genus Anthracotherium is 

 indeed missing in this locality, but it certainly lived at the same time as 

 Ancodus, which is so characteristic of Ronzon, as proved by the discovery of 

 the two together at Hampstead, in the Isle of Wight. Contemporaneous 

 with the marls of Ronzon are the Bohnerz of Vehringen and Ulm, the 

 limestone of Brie, the sands of Fontainebleau, a large part of the phosphorite 

 of Quercy, the lignite of Dalmatia and Northern Italy — Monte Bolca, Monte- 

 viale, and of Bohemia, and the asphalt deposits of Lobsann in Alsace. 

 The locality of Calaf, near Barcelona, is of special interest, because here 

 Biplohune also occurs in association with Ancodus. Besides Dijjlohune there 

 also range upwards from the Eocene into the Oligocene Paloplotherium and 

 presumably Palaeotherium ; among smaller artiodactyls, Amphimeryx, Gaeno- 

 therium, and Plesiomeryx, with Metriotherium, Dichobune, and Tapirulus ; among 

 carnivores, Hyaenodon, Amphicyoninae, and Cynodontinae — the supposed fore- 

 runners of the bears ; among rodents, Theridomys, Sciuroides, and Pseudosciurus ; 

 among itisectivores, Erinaceinae ; and marsupials. Hence, if these forms are 

 regarded as of prime importance, it may be said that we are dealing merely 

 with an impoverished Eocene fauna. Nevertheless, while these earlier ele- 

 ments, such as the Eocene types of perissodactyl, are gradually becoming 

 extinct, there is no inconsiderable development of new forms ; there appear 

 rhinoceroses — among them Caclurcotherium — Protapirus, Chcdicotherium, fore- 

 runners of the deer — Gelocus, Bachitherium, Prodremotherium — and of the pigs 

 — Pcdaeochoerus, Doliochoerus — also the genera Anthracotherium, Ancodus, and 

 Elotherium ; and among carnivores, a small Hyaenoclon, numerous mustelines — 

 Palaeoprionodon, Stenogale, Stenoplesictis, Plesictis — besides forerunners of bears — 

 Cynodon, Pachycynodon and Cephalogale. There also belong first to the Lower 

 Oligocene the numerous insectivores, bats, and the greater part of the rodents 

 from the Phosphorites, chiefly Theridomys, but also Protechimys, Nesolcerodon, 

 Cricetodon, and Eoniys. 



The next younger fauna — Stampian — from the marls of Cournon, Peublanc, 

 and Gergovia, in the Auvergne, St. Henri near Marseilles, and Briatexte 

 (Tarn), forms indeed the continuation of the fauna of Ronzon, as shown by 

 the presence of the last Hyaenoclon and the higher stage of development of the 

 rodents — Archaeomys, Issiodm'omys, — but it is incomparably poorer in species. 

 The most important forms are a large Anthracotherium with nearl}^ unreduced 

 side toes, Lojjhiorneryx — which also occurs in the Cyre7ia-yxiarh of the Mainz 

 Basin — besides Dremotherium and Amphitragidus and the first Ochotonidae — 

 Titanomys. With these there still occur Caenotherimn and Plesiomeryx, as well 

 as Pcdaeochoerus, Bhinoceridae and Tapiridae. 



The youngest Oligocene fauna is that of La Milloque, Gannat, to which 

 the mammalian remains from the lignites of Gadibona, Rochette and Rott 

 belong. It has yielded only few species, among which, however, the true 

 Anthracotherium magnum and the small Microhunodon are of special importance 

 on account of their abundance. A large part of the European Oligocene, 

 moreover, is of marine origin, and is then characterised by numerous remains 



