S94 W. B. DAWKIlfS ON THE CLASSIFICATION" OF THE 



15. The Characteristic Upper-Pliocene Forms. 



The study of the Upper-Pliocene Mammalia presents the foUoAving 

 important characteristics. The Hippopotamus amphihius was widely 

 distributed through the forests of Prance and Italy ; and numerous 

 deer of the section Axeidse are probably identical specifically with 

 the deer of Southern and Eastern Asia, of the types of Axis, Busa, 

 and Cervus taivanus *. Hipparion appears for the last time ; 

 and with the extinction of Macacus florentinus the family of apes 

 passed away from among the European fauna. The disappearance 

 of the apes from Europe at the close of the Pliocene age is one of 

 the most important facts in the history of the fossil mammals. In 

 the Upper Miocene they ranged as far north as Eppelsheim. In 

 the Lower Pliocene they were restricted to the forests of the south 

 of Erance, and in the Upper Pliocene to those of Italy. Their 

 southern retreat and final extermination in Europe are probably 

 due to a climatal change, to a lowering of the temperature, which 

 arrived at its minimum in the Pleistocene age. 



The evidence as to the presence of man in the Italian Pliocenes, 

 brought forward by Dr. Cocchi f and Prof. Capellini J, seems to me 

 to be unsatisfactory. The Pliocene Mammalia are not sufficiently 

 specialized, do not contain a sufficient number of living species, to 

 make it probable that man belonged to the Pliocene fauna. 



The four most important new living genera are the oxen, the 

 horses, the bears, and the elephants. The first of these. Bos etruscus, 

 was sometimes without horns, as in a skull pointed out to me in 

 1877 by Dr. Eorsyth Major in the museum at Elorence. This 

 interesting specimen renders it likely that horns were originally a 

 sexual character peculiar to the bulls, transferred afterwards to the 

 cows. The cows, however, possessed horns in the succeeding Pleis- 

 tocene age, in the deposits of which fossil polled cattle are unknown. 

 If this view of the origin of horns be accepted, it is easy to explain 

 the singular ease with which the horns have been bred out of some 

 -of the domestic cattle, in^a comparatively short time, by selection 

 carried on through a few generations, and our polled cattle may be 

 looked upon as a reversion to an ancestral type. The small size 

 ^Iso of the tusks of the domestic hogs, as compared with those of 

 the wild boar, may be explained in the same manner. 



The horses inhabiting the Val d'Amo in the Upper-Pliocene age 

 were intermediate in the structure of their feet and teeth between 

 the common horse and the Hipparion, and may perhaps indicate 

 that the deposits in which they occur are later than those of Au- 

 Tergne with the remains of Hipparion. The elephants are repre- 

 sented by the Mephas meridionalis of the Upper Pliocene of France 

 and Italy. The bears are small, and with the canine teeth not so 

 large as in the Pleistocene Ursus arctos and U. spelceus. 



* Dawkins, Quart. Journ. Geo! Soc. vol xxxiv. p. 402. 



t Mem. della Soc. Ital di Sc. Nat. ii. no. 7, 1867. 



\ Atti della Eeale Accad. del Lincei, ser. 2, torn. iii. 1876. 



