162 BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 



Peters, A. rami* (Miller), A. rosenbergi Thomas, A. toltecus Saus- 

 sure, A. watsoni Thomas. 

 Remarks. — According to the presence or absence of the vanishing 



last molars, the species may be arranged as follows: Molars g, 

 planirostris ; molars |, coryi, glaucus, intermedins, jamaicensis, 

 lituratus, palmarum, parvipes, rosenbergi, watsoni/ molars g> 

 cinereus, phwotis, quadrivittatus, ravus, toltecus. The species of 

 the first group has been associated with the very different Uroderma 

 bilobatum, those of the second are Artibeus in a restricted sense, 

 while those of the third have been called Dermanura, either as a 

 subgenus of Artibeus or as a distinct genus. After examining prac- 

 tically all the known species, I can see no good reason for subdi- 

 viding the genus Artibeus further than by removing Uroderma and 

 Enchisthenes. There appear to be no other characters correlated with 

 the different tooth formulas; and the presence or absence of these 

 terminal teeth, when reduced to the vanishing point and entailing no 

 change in the form of the surrounding bone, is of little importance. 



Genus ENCHISTHENES Andersen. 



1906. Enchisthenes Andersen, Ann. and Mag. Nat. Hist., 7th ser., XVIII, p. 

 420. December, 1900. 



Type-species. — Artibeus harti Thomas. 



Geographic distribution. — Island of Trinidad, West Indies. 



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



Characters. — Similar to Artibeus, but inner upper incisor not bifid, 

 and third molar both above and below well developed and effecting 

 the form of the surrounding bone. 



Species examined. — Enchisthenes harti (Thomas). 



Remarks. — This genus is well differentiated from Artibeus by the 

 simple form of the inner upper incisor and the large size of the pos- 

 terior molar in both upper and lower jaws. The only species at 

 present known is further distinguished from the members of the 

 genus Artibeus by the presence in the tragus of " a pointed upwardly 

 directed projection on the inner margin near the tip." 



Genus ARDOPS Miller. 



1891. Sienoilerma Thomas, Ann. and Mag. Nat. Hist, 6th ser., VII, p. 529. 



June, 1891 (part). 

 1898. Stenoderiim Trouessart, Catalogue mammalium, p. 162 (subgenus, 



part). 

 1906. Arilopx Miller, Proc. Biol. Roc. Washington, XIX, p. 84, June 4, 1906. 



Type-species. — Htenode una rue/tolls! Thomas. 

 Geographic distribution. — Lesser Antilles. 



