112 CLASS MAMMALIA. 



an ample and profound pouch, which constitutes a conve- 

 nient envelope for the young bats which are yet suckling, 

 and a place of shelter where they find all the protection 

 and all the heat necessary for their security and develop- 

 ment. 



We shall next speak of the Cephalotes, two species, 

 one described by Pallas, and another discovered by M. 

 Peron, which have a close affinity with the roussettes, but 

 yet differ sufficiently to constitute a separate sub-genus. 

 They have the conical head, the sharp muzzle, the ears with- 

 out tragers, the short index provided with all its phalanges, 

 the shortness and particular position of the interfemoral 

 membrane, the small tail, the papillous tongue, and the 

 remarkable form of the molar teeth peculiar to the rous- 

 settes. But they differ in other points. Their head is 

 shorter and larger than that of the others, and the face still 

 more than the cranium. The latter retreats more and is 

 narrower in front. The teeth are but twenty-eight, four 

 incisors, four canines, and twenty molars, eight of which 

 are in the upper jaw and twelve in the lower. Thus the 

 incisives are but half as many as in the roussettes, nor is 

 this occasioned by too close an approximation or too ex- 

 cessive a development of the canine teeth. The upper 

 incisors are at a certain distance between them, and per- 

 fectly isolated, which, however is not the case with the 

 lower. 



Such an anomaly in a character of this importance cannot 

 exist alone. Those who are most superficially acquainted 

 with the laws of Zoology, are aware that such a modifica- 

 tion produces others. This is the consequence of what our 

 author has termed the subordination of characters. Every 

 thing in the organization of an animal is connected, and 

 without knowing why or wherefore, we always find a cor- 

 relation to exist, even where it is impossible to perceive 

 any necessary connexion. 



