422 THE AGE OF MAMMALS 



moth, distributed in eastern Europe, Germany, and southern Siberia. 

 Whether it reached northern Siberia with the mammoth, woolly rhinoceros, 

 musk ox, and reindeer remains an open question. To the south, teeth have 

 been attributed to this animal from Sicily. ^ It is a gigantic animal distin- 

 guished from all the European Pleistocene forms by the absence of the 

 anterior horn and possession of an enormous horn situated on the forehead 

 between the eyes, and by the elaborate foldings in the enamel of its teeth. 

 It is possibly descended ? from the typical Aceratherium of the Upper 

 Miocene of Eppelsheim (p. 272), which shows the rudiment of a horn be- 

 tween the eyes. The skull attains a meter in length ; the dermal horn on 

 the forehead was enormous. The limb bones exceeded in size those of the 

 largest species of rhinoceros by one-third in length. Its hypsodont and 

 folded teeth were especially adapted to a grassy diet, and Gaudry connects 

 its appearance in Europe with the extensive deforestation accompanying 

 the steppe and tundra periods of mammalian hfe; it apparently wan- 

 dered into Europe from central Asia and never became very numerous. 



Reindeer or caribou. — The reindeer of Eurasia and America embrace 

 two groups of species, the 'barren ground' and the 'woodland,' readily 

 distinguished by the size and the proportions of the antlers.^ The barren 

 ground reindeer is said to have entered Europe with the second fauna 

 and perhaps came by a different route (i.e. via Greenland).* The wood- 

 land first appears in Europe with the third fauna, and persisted until com- 

 paratively recent times, but has now become extinct. In the barren 

 ground, typified by the Old World reindeer (R. tarandus, R. spitzhergensis), 

 and by the American arctic forms (R. arcticus, R. groenlandicus, R. granti, 

 R. pearyi), the antlers are round, slender, and long, in proportion to the 

 relatively small size of the animal, while the beam and the tines, including 

 the brow tine, are, as a rule, but little palmated; in some forms the ' brow 

 tine ' is palmate. The antlers of the woodland group, now extinct in 

 Europe, but typified by several American species (R. caribou, R. monianus, 

 R. osborni), are heavier, flatter, thicker, and more heavily palmated, both 

 on the beam and tines, especially the brow antler, while the tine above 

 the 'brow,' corresponding to the 'bez-tine' of the stag (Cervus) is elaborately 

 developed and palmated, contrasting sharply with the same tine in the 

 barren ground group. 



Carnivores. - — Probably the chief enemies of the Herbivora were the 



1 Brandt, J. F., Mittheilungen (iber die Gattung Elnsmotherium, besonders don Schildel- 

 bau dersclben. Mem. Acad. Imper. Sci. Pelershourg, Ser. VII, Vol. XXVI, no. G, St. Peters- 

 burg, 1878; and Gaudry and Boulo, Materiaux pour I'Histoire des Temps Quaternaires. 

 Si^me Fasc. L'Elasmotherium. Paris, 1888. 



2 Osborn, H. F., Frontal Horn on Aceratherium incisixum. Relation of the Type to Elas- 

 motherium. Science, n.s.. Vol. IX, no. 214, Feb., 1899, pp. 161-162. 



3 Grant, Madison, The Caribou. Ann. Kept. N.Y. Zool. Soc, no. 7, New York, 1892, 

 pp. 17.5-19G. 



^ Scharff, R. F., The History of the European Fauna, London, 1899, p. 154. 



