SUB-ORDER. 



,., .',,,,.. CARNIVORA. 



Incisors aix in each jaw ; the lateral ones largest. Canines distinct, conical. Clavicles imperfect or wanting. 



The above phrase characterizes the great division of the Camivora as to its essential points. 

 The Insectivora, to which they are closely allied, have the central incisors as large or larger 

 than the lateral ; the canines less distinct ; the clavicles perfect. There are many other features, 

 however, in which the Camivora exhibit their claim to a separate subdivision of the animal 

 kingdom. 



Osteologically the Camivora are characterized by the fact that the clavicles are either want 

 ing or else quite rudimentary. There are six incisors in each jaw, the outer the largest. There 

 is a distinct canine on each side of each jaw, just behind the incisors; they are generally very 

 large, conical, and deeply implanted by a single fang (in the upper jaw just behind the inter 

 maxillary). The incisors and canines vary but little, comparatively, in the different genera 

 and families. The molars, on the contrary, differ very much as to number and shape. In this 

 character is a striking difference from the Insectivora, where, with a nearly constant type of 

 molars, the canines and incisors differ exceedingly. 



As a general rule it is the premolars of the Camivora which play the most important part in 

 the series of cheek teeth. In nearly all of the families, one of these on each side, in each jaw, 

 is so arranged with compressed and cutting crowns, that those of opposite jaws, on either side, 

 play against each other and serve to divide the food like a pair of shears. Others have, either 

 in addition to, or instead of this arrangement, molars with tuberculous crowns for more readily 

 crushing bones or other hard substances. Immediately behind each canine are one or more 

 comparatively small teeth, with conical or compressed crowns, and simple or double fangs. 

 These are often absorbed or wanting in age. Next come the sectorial teeth, as described above. 

 Behind the sectorial teeth are one or more teeth with tubercular crowns. Tho habits of the 

 species depend much on the relative number and development of these two kinds of molars, 

 whether trenchant or tuberculous ; when the former predominate, the food is more exclusively 

 the flesh of animals, while the opposite condition indicates sustenance of a more mixed nature. 



The order of Camivora is usually divided into six families: the Felidae, Hyaenidae, Canidae, 

 Viverridae, Mustelidae, and Ursidae. Of all these, North America possesses representatives, 

 excepting the Hyaenidae. Of the Viverridae there is but one genus known in America, namely, 

 Bassaris. At one time it was believed that fossil remains of Hyaenidae occurred in the bone 

 caverns of Brazil ; these are now with more probability referred to a genus Smilodon, very 

 closely allied to, if not identical with, MacJiairodus, an extinct genus of Felidae, first discovered 

 in Europe, but recently shown by Dr. Leidy to exist in the Mauvaises Terres of Nebraska. 



The North American families may be grouped as follows : 



A. DIGITIGRADE. Hinder feet with four toes. 

 Felidae. 

 Canidae. 



