134 UNGULATA order vii 



septum. Manus tetradactyl ; pes tridactyl. Now living in South and 

 Central America and East Asia. Fossil tapirs were widespread in the Miocene 

 and Pliocene of Europe : Tapirus telleri Hofmann, Upper Miocene of Styria ; 

 T. prisms Kaup, Lower Pliocene of southern Germany ; T. Imngaricus Meyer, 

 Middle Pliocene of Styria and Hungary ; T. arvernensis Croizet and Jobert, 

 Upper Pliocene of Auvergne. A gigantic tapir, Tapirus sinensis Owen, lived 

 during the Pleistocene in China. In the Pleistocene of North America occurs 

 Tapirus hay si Leidy ; and Tapirus tarijensis Ameghino is known from the Pleisto- 

 cene of Bolivia. 



Family 2. Rhinocerotidae Gray.^ 



Nasal hones standing out freely, often with a rugose cushion for one or two horns. 



Narial openings much prolonged backward. Dental formula: ' • 



Incisors and canines sometimes wanting. Premolars more or less molariform, less 

 complex only in the oldest forms. Upper molars with thick ectoloph, without a median 

 fold, and with two oblique gently curved transverse ridges intimately connected with 

 the ectoloph. Inferior cheek teeth with two ridges bent at right angles, the posterior 

 of which unites with the protolophid at the antero-external corner. Third molar 

 without talon. Manus with three or four digits. 



To the Rhinocerotidae belong chiefly large heavy herbivorous quadrupeds, 

 with a short neck, short legs, and a short tail. They still exist in the low 

 swampy grounds of tropical India, the Sunda Islands, and in Central Africa. 

 The fossil forms appear in the Middle Eocene of Europe and North America, 

 and in the Miocene, Pliocene and Pleistocene had spread over the entire 

 Northern Hemisphere and Northern Africa. They are characterised in part 

 by the presence of stout horns, which originate as true epidermic structures 

 from agglutinated tufts of hair, and are borne on rugose pad-like protuber- 

 ances of the nasal bone, sometimes also of the frontal bone. If two horns 

 are present, they are usually arranged one behind the other, more rarely side 

 by side (Diceratherium). 



Only in the earliest types is the dentition complete ; in the later forms 

 the canines first become aborted, and afterwards the incisors. In the older 

 forms, either all or the two anterior premolars are much less complex than 



■^ Abel, 0., ttber die palaogenen Rhinocerotiden Enropas. Abhandl. k. k. geol. Reiclisanst., 

 XX., 1910. — Brandt. J. F., Mem. Acad. Imp. Sci. St-Petersbourg, vol. viii., 1864; vol. xxiv., 

 no. 4, 1877 ; and vol. xxvi., 1878. — Cope, E. D., Ou the American Rhinoceroses and their allies. 

 Amer. Nat., p. 770, 1879. — Douglass, E., Rhinoceroses from the Oligocene and Miocene of North 

 Dakota and Montana. Ann. Carnegie Mus., vol. iv., 1908. — Duvernoy, G. L., Nonvelles etudes 

 sur les Rhinoceros fossiles. Arch. Museum Paris, vol. vii., 1853. — Flower, W. H., On some 

 cranial and dental characters of the existing species of Rhinoceroses. Proc. Zool. Soc. London, 

 p. 443, 1876. — Hatcher, J. B., New fossil Vertebrates. Ann. Carnegie Museum, 1907. — Meyer, 

 H. von. Die diluvialen Rhinoceros-Arten. Palaeontgr., Bd. xi., 1864. — Niezahitowski, L., Die 

 Uberreste des in Starunia gefuudenen Rhinoceros autiquitatis. Bull. Acad. Sci. Cracovie, 1911. 

 —Osborn, H. F., The Extinct Rhinoceroses. Mem. Araer. Mus. Nat. Hist., pp. 79-164, 1898.— 

 Phylogeny of the Rhinoceroses of Europe. Bull. Amer. Mus. Nat. Hist., pp. 229-267, 1900.— 

 Pavlow, Marie, Etudes sur I'liistoire paleontologique des ongules. III. Rhiuoceridae et Tapiridae. 

 Bull. Soc. Imp. Nat. Moscou, 1888 ; VI. Les Rhinoceridae de la Russie et le developpement des 

 Rhinoceridae en general. Ibid., 1892. — Peterson, 0. A., A mounted skeleton of Diceratherium 

 cooki. Ann. Carnegie Mus., vol. vii., 1911. — Weber, M., Uber tertiiire Rhinocerotiden der Insel 

 Samos. Bull. Soc. Imp. Nat. Moscou, 1904, 1905. — Roman, F., Le Cadurcotherium. Arch. 

 Mus. Lyon, 1908. — Toula, F., Das Nashorn von Hundsheim. Abhandl. k. k. geol. Reichsanst., 

 1902, 1906.— 5co«, W. B., Osteologie von Hyracodon. Festschr. f. Gegenbaur, 1896. 



