LEPUS. 121 



Lepus nigricaudatus, Bennett P. Z. S., p. 41 (1833). 



Lepus texianus, Waterhouse Nat. Hist. Mamm., ii, p. 136 (1848), 



The Jackass Hare. 



Distribution. — Southern parts of the United States and Mexico 

 to the isthmus of Tehuantepec. 



a. Skin Nuces Valley, Texas, 2-84 J. H. Gamier [Ex.] 



Order UNGULATA. 



Placental Mammals with no clavicles ; with limbs for progres- 

 sion only ; the ist digits of all recent forms wanting; ungual pha- 

 langes hoofed ; metacarpals and metatarsals vertically elongat- 

 ed or sharply inclined ; teeth covered with enamel and molars 

 generally complex. 



Key of the Indian Genera. 



Digits of manus and pes equal or even in number ; the 3rd 

 digit of each foot asymmetrical in itself, but forms with the 

 4th digit a symmetrical pair; no 3rd trochanter to the femur, 

 posterior premolars smaller and simpler than the molars ; 

 stomach complex ; caecum small ; horns when present paired. 



[=Artiodactyla.] 



h. Ulna and fibula incomplete, confluent with radius and tibia, 

 manus and pes functionally didactyle ; incisors rarely pre- 

 sent in the upper jaw ; lower canines incisiform ; premolars 

 and molars with uni- or bicrescentic ridges ; stomach 

 complex, four-chambered and ruminating. 



[=Selenodontia.] 



c. Horns generally present ; the third and fourth metacarpals 

 and tarsals fused to form a cannon bone ; digits- two and 

 five, incomplete and wanting. [=Cotylophora.] 



d. Horns hollow and persistent; digits two and five repre- 

 sented by hoofs only ; no upper canines ; gall bladder 

 present. [=Bovid3e, see key below.] 



^2. Horns solid and deciduous ; digits two and five have 

 distinct metacarpals and phalanges ; no gall bladder. 



[=Cervidse.] 



e. Horns small ; upper canines well-developed ; distal 

 tarsal elements all united except an ectocuneiform. 



Cervulus, p. 172, 



