Vol. 6] Mcrriam: Virgin Valley and Thousand Greek 



249 



URSIDAE( ?) 



URSUS(?), sp. 



A large terminal phalange, no. 

 12554 (fig. 20), from the Thousand 

 Creek Beds at locality 1100 at Thou- 

 sand Creek, closely resembles the term- 



inal phalanges of the bears, but may 12554, natural size. Thou- 

 , . , r. sand Creek Beds, Thousand 



represent a very large canid rorm. Creek Nevada. 



MUSTELIDAE 

 MUST EL A FURLONG I, n. sp. 



Type specimen, a lower jaw fragment with complete carnas- 

 sial tooth, no. 12540, Univ. Calif. Col. Vert. Palae. From Thou- 

 sand Creek Beds; locality 1103, Thousand Creek, Humboldt 

 County, Nevada. 



In the collections from near Thousand Creek there are two 

 fragments of lower jaws with carnassials which represent an ex- 

 ceedingly small musteline species. The mandible of the smaller 

 specimen measures only about three and one-half millimeters in 

 height below the carnassial. The jaws are also apparently 

 rather slender, and the anterior end of the masseteric fossa does 

 not extend as far forward as in most of the modern forms. (See 

 figs. 22« and 22b). 



Mj possesses a well developed metaconid and a long basin-like 

 heel. The metaconid is relatively a little larger than in the 

 modern species of Mustela. The long, wide heel is bordered by 

 a prominent horseshoe-shaped marginal wall. M 2 is not present, 

 but the tooth must have been much reduced, as the alveolus for 

 the single root is small. P 4 , as shown in specimen 12540, is two- 

 rooted. 



This species is somewhat more primitive than the Recent 

 Mustela in the form of the trigonid of M x , while the inner wall 

 of the heel of this tooth is somewhat higher. More complete 

 material may show that this form is generically distinct from 

 the species grouped under the typical Mustela. In view of its 



