THE FAMILIES AND GENERA OF BATS. 99 



Remarks. — Except from the next genus Noctilio is so readily dis- 

 tinguishable that it requires no special comparison with any known 

 group of bats. Externally it is perhaps most easily recognized by 

 the excessively long legs and large feet, heavy, bony calcar, and long 

 terminal phalanx of third finger, flexed under metacarpal; but its 

 strongly wrinkled lips, sharp muzzle, and pointed, erect ears are 

 also highly characteristic. In most of its peculiarities, undoubtedly 

 to a considerable degree correlated with its largely fish-eating habits, 

 Noctilio is the more specialized of the two genera comprised in the 

 family. 



Genus DIRIAS Miller. 



1S78. Hoctilio Dobson, Catal. Chiropt. Brit. Mus., p. 293 (part). 

 1904. Dirias Miller, Proc. Biol. Soc. Washington, XIX, p. 84, June 4, 1906 

 (albiventer). 



Type-species. — Noctilio albiventer Spix. 



Geographic distribution. — Warmer parts of South America. 



Number of forms. — Dirias albiventer (Spix) and D. zaparo (Ca- 

 brera). 



Characters. — Like Noctilio externally but with less elongated leg 

 and foot, the length of tibia and foot together scarcely exceeding 

 40 per cent of the " total length." Skull as in Noctilio. Teeth as in 

 Noctilio except that the first and second upper molars are very 

 slightly emarginate posteriorly, so that the spaces between the teeth 

 are scarcely noticeable; hypocone relatively largely than in Noctilio 

 and connected by a high, conspicuous commissure, with the commis- 

 sure extending from protocone to metacone. 



Species examined. — Dirias albiventer (Spix). 



Family NYCTEEID^. 



1821. Vespertilionidw (part; Race 1, part) Gray, London Medical Reposi- 

 tory, XV, p. 299, April 1, 1821. 



1827. Rhinolophina Lesson, Man. de Mammalogie, p. 81 (part). 



1831. Vespertiliones (Vespertilionida;) (part; Phyllostomina, part) Bona- 

 parte, Saggio di una distrib. metodica degli Anim. Vert., p. 15. 



1838. Vespertilionidw (part; Rhinolophina, part) Bonaparte, Nuovi Annali 

 delle Scienze Naturali, Bologna, Anno I, Tomo II, p. 112. 



1838. Vespertilionidw (part; Vespertilionina, part) Gray, Mag. Zool. and 

 Bot, II, p. 494, December, 1838. 



1854. [Rhinolophida;] " Rhinolophides " Gervais, Hist. Nat. des Mainmi- 

 feres, p. 200 (part). 



1855. Nycterina Van der Hoeven, Handb. der Dierkunde, 2d ed., II, p. 1028 

 (part). 



1865. Megadermata Peters, Monatsber. k. preuss. Akad. Wissensch., Berlin, 

 p. 256 (part). 



1866. Rhinolophidce (part; Nycterina) Gray, Proc. Zool. Soc. London, p. 83. 

 1872. Megadermidw Gill, Arrangement of the Families of Mammals, p. 17 



(part). 



