154 ORDER V. 



The domestic races intermix freely with the cre- 

 puscular Canidce of America, which have elliptical 

 pupils. 



Sub-genus CHRYSOCYON, Aguara Wolves. 



Sub-genus DUSICYON, Aguara Dogs. 



Sub-genus CERDOCYON, Aguara Foxes, 

 which again pass imperceptibly into true foxes, with 

 elliptical pupils, that dilate and contract with facility; 

 and, therefore, are more particularly nocturnal. 



Sub-genus VULPES. Foxes. The first form, or 

 Arctic Foxes, is still indifferently capacitated to con- 

 tract the pupils ; but the True Foxes of the Old Con- 

 tinent and of the New, possess the faculty com- 

 pletely. They may be divided into two groups in 

 each continent, distinguishable by the tips of the 

 tails being either black or white. 



Sub -genus LYCAON, of which only one species is 

 known, externally resembling the hyenas, and at 

 first named Hycena venatica; it is the Lycaon tri- 

 color of Brooks, and has four toes on all the feet. 



Genus HY^NA has the same general form of 

 skull as the Canidae, with the posterior portion 

 more produced ; the bony palate prolonged further 

 back, and the small back molar of dogs wanting, 

 there being only five molars on each side above, and 

 four below ; four toes on all the feet, and a glan- 

 dular pouch beneath the tail, which evinces approx- 

 imations towards the civet group of the next family. 

 There are four or five species known; and fossil 

 hya3na skulls, abundant in cases of the recent ter- 

 tiary period, attest that there was a time when they 



