THE FAMILIES AND GENERA OF BATS. 



89 



minute tufts of grayish fur, a character of much use in identifying 

 specimens. 

 Species examined. — Rhynchiscus naso (Wied). 



is a 



Genus SACCOPTERYX Illiger. 



1811. Saccopteryx Illiger, Prodr. Syst. Mamrn. et Avium, p. 121 (leptura). 

 1838-39. Urocryptus Temminck, Van der Hoeven's Tijdschr. Nat. Gesch. en 



Physiol., V, p. 31 (Wttneata). 

 1878. Saccopteryx Dobson, Catal. Chiropt Brit. Mus., p. 369- (part). 



Type-species. — Vespertilio leptura Schreber. 



Geographic distribution. — Mainland of tropical and subtropical 

 America. 



Number of forms. — About half a dozen species of this genus have 

 been described. 



Characters. — Teeth as in Rhynchiscus, except that pm 

 simple terete spicule, and the outer 

 anterior cingulum cusp of m 1 is less 

 developed. Skull (fig. 14) with 

 broad flat rostrum considerably more 

 than half as long as brain case, and 

 so low posteriorly as to form a dis- 

 tinct angle with forehead. Sides of 

 rostrum very slightly inflated and 

 median groove obsolete. Lower rim 

 of orbit so expanded as to hide tooth 

 row when viewed from above. Pre- 

 maxillaries large, expanded poste- 

 riorly, and terminating on dorsal 

 surface of rostrum by an abruptly 

 truncate margin. Postorbital proc- 

 esses large, broad, and flat. Brain 

 case with distinct sagittal crest. 

 Basisphenoid pits large, well de- 

 fined, separated in middle by a distinct longitudinal plate. Audital 

 bulla not as large as area of the pits, slightly but distinctly emar- 

 ginate antero-internally. Externally distinguished by the presence 

 of a glandular sac opening on upper surface of antebrachial mem- 

 brane close to forearm near elbow. The sac is conspicuous in males, 

 less developed in females. 



Species examined. — Saccopteryx bilineata (Temminck) , S. leptura 

 (Schreber), S. canescens Thomas, S. gymnura Thomas, S. centralis 

 Thomas. 



Fig. 14. — Saccopteryx bilineata. Catjra, 

 Teinidad. No. 6102, Ameb. Mus. Nat. Hist. 

 x2. 



