26* ZOOLOGY OF THE VOYAGE OF THE SULPHUR. 



dry specimen to have been frequently folded across at the knee-joint, forming 

 a kind of pouch in front, when the feet are bent up. The tail is elongate,* formed 

 like the tail of other Noctilionina, and extending about half the length of the 

 interfemoral membrane, the apex being on the upper surface ; the basal joints 

 are of the usual form ; the two last joints, on the contrary, are expanded, hollow, 

 horny, and black, the penultimate joint being broad and crescent-shaped ; the 

 last joint triangular, cordate, and fitting into the crescent in the hinder edge 

 of the preceding joint. These joints are surrounded by very thin skin ; the. joint 

 immediately before them tapers in front ; the folds in the membrane before re- 

 ferred to, come between the two concave joints of the tail, so that when the mem- 

 brane is bent up, one must be folded against the other. The ears are large, 

 rounded, nakedish, hairy at the base externally ; the front of the upper 

 part of the conch being bent down and attached to the face over the eyes, 

 the lobule is continued and produced in front of the chin to under the eyes, 

 but scarcely raised or separated from the rest of the conch by a notch ; the tragus 

 is moderate, rounded at the end, contracted at each side at the base. The hairs 

 of the back are pure white to the base, those of the under surface are lead-colour 

 for the lower third of their length, the rest being white like those on the back. 

 The colour of the fur is peculiar, as being very rare among mammalia, except 

 those which are kept in confinement, or are afflicted with the albino disease, 

 or live in the regions of perpetual snow. It is indeed the only example which 

 occurs to me of a tropical species of Mammalia being of that colour. 



This specimen, brought home by Captain Sir Edward Belcher, C.B., was 

 caught by Mr. Barclay, the botanical collector who accompanied the Voyage, on 

 the 27th of March, 1837, at Pueblo Nuevo, in Central America. It appears to 

 be only the second specimen of this peculiar Bat which has hitherto reached 

 Europe. 



From the examination of the figure given by the Prince de Wied, I was in- 

 duced to arrange this genus, with doubt, at the end of the Vespertilionina; but the 

 examination of the specimen has shown that its proper place is near the Emballo- 

 jiurts, being even more typically Noctilionine than them in having such very long 

 and narrow wings. 



Centueio. 



Centurio, Gray, Ann. and Mag. Nat. Hist. 1842, 259. 



Head rather large. Face flattened and covered with various symmetrical pleats; chin pro- 

 duced; lip ciliated within at the angle of the mouth; nostrils separate, placed on each> 



* Misled by the figure in my " Revision," I erroneously stated the tail to be very short ; and M. de Blain- 

 ville (Ann. Sci. Nat. viii. 362) described it as having no tail 



