252 THE AGE OF MAMMALS 



North American Upper Oligocene anchitheres. Most surprising is the new, 

 broad-headed rhinoceros (7". aurelianensis) , named Teleoceras by Hatcher^ 

 from the presence of a horn at the very tip of its nasals, with a rudiment 

 of a second horn in the center of the frontals, as observed by Gaudry. This 

 animal is in all probability from northern Asia, and is destined to become 



Fig. 127. — Skulls of the French and American teleocerine rhinoceroses. (,4) TclcoccraH 

 aurelianensis (cast), {B) Teleoceras medicornutus (original). In the American Museum of 

 Natural History. 



one of the most distinctive and widespread of Miocene rhinoceroses; al- 

 though short-footed, or brachypodal, and short-limbed, it was a great 

 traveler; its range extended to Florida. The small narrow horn at the 

 tip of the snout was probably an effective defensive weapon. The acera- 

 theres, or hornless companions of Teleoceras, are distinguished by relatively 

 slender limbs and tetradactyl fore feet; the nasals are narrow, pointed, 

 and typically smooth, but they occasionally show the rudiments of a small 

 horn. These animals are decidedly dolichocephalic. As above noted, in 

 the Burdigalian beds of Portugal there occurs a third phylum of rhinoc- 

 eroses, a diminutive form (Dicerorhinus tagicus) ^ distinguished by horns 

 on both the nasals and frontals, and remotely ancestral to the existing 

 rhinoceros of Sumatra.^ We shall speak of these animals as Sumatran 

 rhinoceroses or dicerorhines. A diminutive ancestor of the dicerorhine 

 phylum has also been recently discovered in the sables de VOrleanais, and 

 Roman * believes that there existed in Europe two phyla of these dicero- 

 rhine rhinoceroses, one of more diminutive size, one of larger size, terminat- 

 ing respectively in the small and the large Upper Miocene races of D. 

 schleiermacheri. 



1 Hatcher, J. B., Amer. Natural, Vol. XXVIII, March, 1894, p. 241. 



2 Roman and Fliche, Le Neog^ne Continental dans la Basse Vallee du Tage (Rive Droite), 

 l^re Pt., Paleontologie. Commis. Serv. Geol. Portugal, Lisbon, 1907, p. 44. 



' Thomas points out that the name Ceratorhinus Gray is preoccupied by Dicerorhinus. 

 * Roman, F., Sur un crane de Rhinoceros. Soc. Linn, de Lyon, Mar. 8, 1909. 



