MUSEUM OF COMPARATIVE ZOOLOGY, 



71 



Another cat, perhaps a smaller individual of the same species, is represented 

 by a phalanx of the median row, which is of the characteristically asymmetrical 

 shape, so as to allow the retraction of the claws. It agrees best in shape with 

 the median phalanx of the fourth posterior digit of the lion, but is much larger, 

 measuring 37 mm. in length, and the proximal end is 20 mm. wide ; in the 

 lion these dimensions are 27 and 14 mm. , 



A third very large feline is indicated by the proximal end of a radius from 

 the Loup Fork of Nebraska : it agrees closely in shape and size with that oi 

 the lion. 



Still another cat is represented by the third and fourth 

 metatarsals from the same horizon and locality. The 

 mode of interlocking, the shape and character of the prox- 

 imal articular surfaces, are very cat-like, but the bones are 

 short and massive, showing strikingly different propor- 

 tions from those to be observed in the recent forms. 



Measurements. 



Fells leo. ? 



m. m. 



Metatarsal III., length 119 .089 



" " width proximal end . .021 .022 



« IV., length 115 .093 



" " width proximal end . .015 .018 



These specimens show that the number of cats occur- 

 ring in the Loup Fork formation is much more consider- 

 able than has hitherto been supposed. Unfortunately, 

 however, these remains are not associated with teeth, so 

 that they cannot be referred to their proper genera and 

 species. 



Figure 5. — Third 

 and fourth metatarsals 

 of unknown feline X £. 



? Pseudalurus intrepidus, Leidt. 



This species is doubtfully indicated by a humerus, lacking the proximal end, 

 which is distinctly feline in character, but remarkable for the very weak de- 

 velopment of the supinator ridge. 



MUSTELID^l. 



Carnivora of this family are not certainly known to occur in any American 

 formation older than the Loup Fork, and they are very rare even in that forma- 

 tion. The mustelines are represented in the collection by only a fragment of a 

 lower jaw supporting pm. 4. In the absence of the molars, it is impossible to 

 determine to what genus this specimen should be referred ; but it would appear 

 to agree best with the Mustela parviloba of Cope. 



