1921] Frick: Faunas of Bautista Creek and San Timoteo CaTion 283 



I. Bautista Creek Area (Pleistocene) 



The Bautista beds, in which have been fonud a large Eqmis some- 

 what resembling that of the Staked Plains, a tapir, a camel, a cervid 

 form resembling Odocoilevs, a small species of antelope near Capro- 

 meryx, a neotragocerine-like form, a megalonj'chid type of ground- 

 sloth, and a rabbit, 



II, San Timoteo Canon Area (Late Pliocene) 



The upper series of deposits, here referred to as the San Timoteo 

 beds, from which has been obtained a fauna containing a very large 

 and a medium size horse of an interesting Pliohippus type approxi- 

 mating Equus, a cervid ( ?), two camels, a megalonychid ground-sloth, 

 and two tortoises, 



III, Eden Area (Upper Division of Lower Pliocene) 



A lower series of deposits referred to as the Eden beds, which has 

 furnished several intensely interesting species of small horse of Plio- 

 hippus form, fragmentary remains of ground-sloths of megalonychid 

 type, of the sabre tooth tiger, and of small species of dogs and cats, a 

 hyaenaretid bear, several large cervid or antelope-like forms, a smaller 

 antelope, two species of peccary, two giant and three or more smaller 

 varieties of camel, a mastodon of Trilophodon type, a species of rabbit, 

 and remains of fish, shells, and wood, 



A coarse deposit has been noted underlying the Eden in the neigh- 

 borhood of Potrero Creek. It has as yet yielded no determinative 

 material. 



The immediate aim of the work was originally purely palaeonto- 

 logical, and the geological sketch in the following pages is offered 

 merely as a setting for the description of the faunas, preliminary to 

 the geological mapping of the region. 



The writer desires to acknowledge particularly his indebtedness to 

 Professor John C. Merriam for much friendly advice and invaluable 

 assistance in critical determinations. 



He wishes also to express his appreciation of the interest shown 

 by Dr. John P. Buvvalda in the geological aspect of the problem, and 

 of the great aid rendered by Dr. Chester Stock in assisting in making 

 comparisons with specimens in the University collections, as for his 

 determination of the ground-sloth remains. He would as Avell 

 acknowledge the painstaking attention of Dr. Stock, Mr. E. L. Furlong, 

 and Miss H. E. Ripley to the manuscript, while in press. 



