THE FAMILIES AND GENERA OF BATS. 133 



Phyllostomus, but ear longer than head, and front and sides of lips 

 and chin thickly beset with small cylindrical warts, most numerous 

 anteriorly. Tail much shorter than femur, appearing on upper sur- 

 face of broad interfemoral membrane. 



Species examined. — Trachops cirrhosus (Spix). 



Remarks. — This genus is at once recognizable by the wart-stud- 

 ded lips and the peculiar position of the small lower premolar. 



Genus CHROTOPTERUS Peters. 



1865. Chrotopterus Peters, Monatsber. k. preuss. Alcad. Wissensch., Berlin, 



p. 505 (genus). 

 1878. Chrotopterus Dobson, Catal. Chlropt. Brit. Mus., p. 469 (subgenus of 



Vampyrus ) . 

 1900. Chrotopterus Allen Bull. Amer. Mus. Nat. Hist., XIII, p. 91, May 12, 



1900 (genus). 



Type-species. — Vampyrus anritus Peters. 



Geographic distribution. — Tropical America, north to southern 

 Mexico. 



Number of forms. — The type is the only species known. 

 Characters. — Dental formula : 



-2 3. 1. --34567 . 2-2 1-1 2-2 3-3_ on 



1--. 1.-2 34 5 6 7* 1-1' C l-l'^ m 3-3' m 3-3 - ^- 



Maxillary teeth essentially like those of Phyllostomus, except that 

 the inner incisors are lower and less projecting, the canine is less 

 distinctly grooved on front surface, the anterior premolar (pm 3 ) 

 is small, crowded outward from the toothrow, and so low that its 

 short cusp barely exceeds cingulum of canine; molars with main 

 cusps large and well developed, bu^ with protocone lower in pro- 

 portion to other cusps, and with paracone and metacone nearer 

 each other than in the normal arrangement, and mesostyle, together 

 with its commissures, notably reduced, so that the W pattern is dis- 

 torted by the lengthening of the posterior limb and the shortening of the 

 two median limbs. Mandibular incisors and canines as in Phyllosto- 

 mus, though the canines more closely approach each other. Anterior 

 premolar (pm ,) with the cusp broad and low, more resembling an 

 angular cutting edge than a true cusp; middle premolar (pm 3 ) mi- 

 nute, crowded completely from toothrow on inner side as in Trachops, 

 so that pm 2 and pm 4 are in contact. Lower molars with the cusps 

 essentially unmodified, except that the hypoconid and entoconid 

 are relatively lower than in Phyllostomus and the paraconid and 

 metaconid of m t are nearer to the protoconid and less distinct from it. 

 Skull essentially as in Phyllostomus, but less angular; rostrum and 

 interorbital region subcylindrical ; paroccipital expansion small but 

 distinct; audital bulla small, covering less than half cochlea, its 

 diameter nearly twice height at inner edge. Externally character- 



