410 ^V. D. MATTHEW PROGRESS IN VERTEBRATE PALEONTOLOGY 



chiefly by the American Museum. ^^ AVliile the two great fossil quarries 

 mentioned above contain complete skulls and skeletons of a limited num- 

 ber of large animals — three or four kinds in each — the Snake Creek 

 quarries contain chiefly fragmentary material of a great variety of ani- 

 mals, no less than 50 genera being on my list at present. They are river- 

 channel pockets and are now known to belong to three distinct faunal 

 zonps. 



Perhaps the most interesting out of a multitude of new forms from 

 these quarries are the upper tooth of an anthropoid primate, Tlesperopi- 

 tliecus, the first of this groujD from the American Tertiary, and the com- 

 plete skeleton of Pliohippus, the earliest one-toed stage in the evolution 

 of the horse. Discovery by Troxell of fine skeletons of Plioliippus"'' and 

 of a Tertiary type of Mastodon in the Pliocene of South Dakota, and by 

 Gidley of a large Pliocene fauna in Arizona, should also be mentioned. 



The series of later Tertiary faunas discovered by exploring parties 

 from the University of California, on the Pacific coast and in the Great 

 Basin provinces, are a most important addition, as the}' are almost wholly 

 new fossil fields. ^^ The material as yet discovered is largely fragmentary, 

 but a considerable series of faunas has been differentiated. 



In the Pleistocene the great outstanding discovery is the La Brea 

 asphalt quarries near Los Angeles, remarkable for the nmnbers, the 

 variet}^, and the fine preservation of the specimens. The discovery of 

 this unique series makes it possible to describe the more characteristic 

 forms from series of dozens, or even hundreds, of complete skulls with 

 proportionate numbers of skeleton bones.^^ 



Primates and Man 

 The most widely interesting field of paleontological research is that 



20 W. D. Matthew and II. J. Cook: (1909.) Bull. Amer. Mus. Nat. Hist., vol. xxvi, 

 pp. 361-41.5. 



W. J. Sinclair: (1915.) Proc. Am. I»liil. Soc. vol. llv, pp. 73-95. 

 W. D. Matthew: (1918.) Bull. Amer. Mus. Nat. Hist., vol. xxxviii, pp. 183-229. 

 H. F. Osborn : (1918.) Mem. Amer. Mus. Nat. Hist., n. s., vol. ii, p. 28 ; Amer. 

 Mus. Novitates, no. 37. 



-'E. L. Troxell: (1916.) Am. .Jour. Sci., vol. xlii, pp. 335-348. 

 H. F. Osborn: (1918.) Equidae of the Oligocene, Miocene, and Pliocene, of North 

 America, iconographic type revision. Mem. Amer. Mus. Nat. Hist,, n. s., vol. ii, p. 162, 

 pis. xxviii-xxx. 



2* J. C. Merriam and others: (1910-1922.) Univ. Calif. Geol. I'ubl.. numerous contri- 

 butions. 



23 F. S. Daggett: (1918.) Notes on I'leistocene fossils from Kancho La Brea. Los 

 Angeles Co. Mus. Hist., Sci., and Art ; Dept. Nat. Sci., Misc. I'ubl. 

 .1. C. Merriam and others : XJt sui>nt. 



W. D. Matthew: (1913.) Amer. Mus. Jour., vol. xiii. p. 291; 1910. ibid., vol. xvi. 

 pp. 45, 469. 



