THE PLIOCENE OF EUROPE, ASIA, AND NORTH AMERICA 367 



Formation. This author visited the Peace Creek region in January, 1891, 

 hoping for an opportunity to observe an inter-stratification of marine beds 

 with those containing mammahan re- 

 mains. This anticipation proved to 

 be well founded, because it produced 

 the following results: the bone beds 

 which are rich in the remains of 

 mammalian life lie between an older 

 marine Pliocene rock below and a 

 newer marine Pliocene bed above, 

 thus, in the opinion of this observer, 

 determining its Pliocene character 

 beyond question (op. cit. p. 133). 



The mammals of these Peace 

 Creek bone beds are much more 

 recent than those of the Alachua 

 Clays of Florida, although they do 

 contain one type in common, namely, 

 an hipparion {H. ingenuum). It will 

 be recalled that Hipparion survives 

 in the Upper Pliocene of Asia, also 

 possibly in the Upper Pliocene of 

 Europe,^ and in the Lower Pleisto- 

 cene of North Africa.- No teleocerine 

 or other rhinoceroses appear in these 

 Peace Creek bone beds. We notice 

 also the absence of camels, which 

 may be due, however, to local causes, 

 because camels were probably flour- 

 ishing at the same time on the West- 

 ern plains and in California. 



The mammalian assemblage, if 

 found without association with Plio- 

 cene marine invertebrates, would cer- 

 tainly have been regarded as of early 

 Pleistocene age rather than late Plio- 

 cene. We owe the description and 

 identification of these remains to 

 Leidy •' in 1899, and they undoubtedly 

 require revision to-day. It is possible 



' Stehlin, H. G., Une Faunc a Hipparion h Perricr, 

 rV, 1904. 



^ Pomel, A., Les Equides. Carte Geol. Algerie, Paleont. Monogr., Algiers, 1897. 



' Leidy, J., Description of Vertebrate Remains from Peace Creek, Florida. Trans. Wagner 

 Free Inst. Sci. Phila., Vol. II, Dec., 1889, pp. 19-32. 



Fig. 171. — Chief fossil mammal deposits 

 of eastern North America. 13. Alachua Clays, 

 Fla. 14. Peace Creek, Fla. 15. Charleston 

 (Ashley River), S. C. 16. Port Kennedy, Pa. 



Bull. Soc. Geol. France, Ser. 4, Vol. 



