620 Bulletm American Museum of Nahwal History. [Vol. XIX, 



tons were taken the previous year, resulting in the finding of 

 additional material of Equus scotti (Nos. 10628, 10629 and 

 10630, American Museum Collection). 



Finishing up the season's work here the party again returned 

 to Clarendon, practically by the same route followed the pre- 

 vious year. 



Expedition of 1901. 



The third expedition to the Staked Plains was made possible 

 by the kind generosity of Mr. William C. Whitney, who do- 

 nated a sum to the American Museum to be used, under the 

 direction of Professor Henry F. Osborn, for the collecting and 

 placing on exhibition of fossil horse material to illustrate the 

 evolution of the horse in America. The object, therefore, of 

 this last expedition was to make a more extended exploration 

 of the Miocene and Pliocene exposures with the hope of 

 obtaining some new material of the three-toed horses of these 

 periods. 



Accompanied by Mr. William Kendal as assistant and Mr. 

 James Morton as cook and teamster, the writer left Clarendon 

 July I, going first to the old locality between Barton Creek 

 and Salt Fork of Red River. Wishing to extend the explora- 

 tions further to the north and east the party continued on 

 north about five miles to the head of Petrified Canon, camping 

 there a few days, then turning east traveled down Whitefish 

 Creek about twenty-five miles to Skillet Creek, making another 

 camp at this place. At the head of Petrified Caiion were 

 found the skulls and parts of skeletons of twelve three-toed 

 horses. Unfortunately, however, the bones were badly 

 crushed and broken and covered with a hard limestone con- 

 cretion which is very difficult to remove without injury to the 

 fossil. 



On the divide east of Skillet Creek the writer obtained three 

 important specimens, a skull and lower jaws of a Mastodon 

 (No. 10673, American Museum Collection) of the M. productus 

 type, both fore feet complete of a second individual (No. 

 10672, American Museum Collection) of the same species, and 

 a skull with a few skeleton bones of the big dog Dinocyon 



