3o8 Bulletin American Museum of Natural History. [Vol. XVI, 



in 1898 in the upper levels of the White River beds appears 

 distinct from P . haydeni. It is smaller, more narrow and 

 elongated, the muzzle more slender. The anterior half of 

 another skull and several jaws, chiefly or all from the same 

 upper horizon, may be referred here, although they approach 

 P. haydeni somewhat more nearly than does the complete 



skull. The distinctive 

 characters are : slender and 

 narrow muzzle, small teeth, 

 internal median fold of 

 enamel on upper molars 

 ' , o, , , ^,.„ c, „ , more deeply mcised and 



Fig. 16. PaltEolagus ? agapetiilus. Skull, nat- '^ ■' 



ural size. No. 8704. White River (Martin Canon mOrC pCrsistCnt tliaU iu P. 

 Beds), Colorado. ^_ 



haydeni. The species ap- 

 pears to be good, on the evidence of some half-dozen speci- 

 mens referred to it and compared with the very numerous 

 P. haydeni specimens in our collections. Whether the type 

 of P. agapetillus is properly referred to it, I am unable to 

 decide; but leave it provisionally. 



Palaeolagus haydeni Cope. 



Tricium annce Cope; Tricium avunculus Cope; Tricium leporinum 

 Cope. 



The additional specimens collected by American Museum 

 parties include no complete skull of this species. The best 

 one, No. 9327, shows a skull shorter and wider than P. aga- 

 petillus or intermedius , brain-case rounder than in either, basi- 

 facial axis bent down about as in P. intermedius, arch heavier 

 than in Lepus ennisianus , the jugal a band of uniform width, 

 thickened at the upper and lower margins. Teeth larger than 

 in P. agapetilhis , less transversely broadened, medial internal 

 furrow less deeply incised or persistent. A scapula, vertebra, 

 and metapodial, associated with this specimen, agree in size 

 with Cope's skeleton material of P. haydeni. 



Palaeolagus intermedius Matthew. 



Type, a nearly complete skull from the upper levels of the 

 White River, at Castle Rock, Cedar Creek, Col. Associated 



