24 Zoology of Colorado 



ing characteristics. We have in Colorado the families Felidae 

 (cats), Canidae (wolves and coyotes), and Mustelidae (skunks, 

 badgers, wolverenes, martens, minks, weasels and others). The 

 cougars or mountain lions were formerly considered to belong 

 to a single species, but this is now divided, although the char- 

 acters used are not very striking. Our Colorado animal is called 

 Felis oregonensis hippolestes of Merriam; "hippolestes" means a 

 robber of horses. The English naturalist Pocock in 1917 pro- 

 posed a new classification of the cats, recognizing a number of 

 genera. Dr. J. A. Allen, in an important paper published in 1919, 

 followed this system, with certain amendments. On the new 

 basis, the mountain lion belongs to the genus Puma of Jardine, 

 and is Puma oregonensis hippolestes. Our other Felidae are the 

 bobcats, the genus Lynx. Three species occur within our limits; 

 the Canada lynx, with very large feet, and the tip of the tail 

 black all round; Bailey's bobcat, with smaller feet, and the black 

 mark at the end of the tail only a crescent; and the mountain 

 bobcat, differing from the last in having two or three blackish 

 bands on the upper side of the tail before the tip. Bailey's bob- 

 cat (Lynx bailcyi) was originally described from Arizona, but 

 has been found in Baca and Las Animas Counties, Colorado. 

 Warren describes the tail as having one blackish and one fulvous 

 band before the black tip. The mountain bobcat (Lynx uinta), 

 was described in 1902 from Wyoming, but it seems to extend all 

 over the mountainous region of Colorado, as far as Custer, Delta, 

 Montrose, Grand and Routt Counties. The Canada lynx, Lynx 

 canadensis, occupies the Hudsonian Zone, in the dense timber, 

 and ranges from Colorado northward. Its large feet enable it 

 to travel rapidly over soft snow, in spite of its weight. But the 

 snowshoe rabbit is similarly provided, and so has a reasonable 

 chance for its life. In past ages, larger cats inhabited Colorado, 

 preying upon the large animals then living. Mr. Harold Cook 

 (1922) has described from the Pliocene of Yuma County an 

 animal with the skull 310 mm. (over a foot) long. It is related 

 to the sabre-toothed tigers, and perhaps preyed upon the ground- 

 sloths, becoming extinct when they perished, though at present 

 we do not know of its survival into the Pleistocene. Its name is 

 Machaerodus or Heterofelis coloradensis. The subgeneric name 

 (Heterofelis) proposed by Mr. Cook will probably be accepted in 



