8/2 MR. G. E. DOBSON ON MYXOPODA AURITA. [Nov. 5, 



Crown of the head but slightly raised above the face-line ; muzzle 

 obliquely truncated, in general form closely resembling that of the 

 species of the genus Chilonycteris ; for the nostrils open widely 

 apart by similar circular sharply defined margins, and the lower lip 

 is also papillate and reflected outwards, though not so broadly, and 

 it has not a thin free margin ; the obtuse extremity of the rather 

 long muzzle projects in front considerably beyond the lower lip. 

 Ears very large, much longer than the head, in general outline like 

 those of Vespertilio murinus ; but the inner margin commences in a 

 small lobe projecting downwards ; in the usual position of the tragus, 

 or slightly in front of it, there is an irregularly square lobe con- 

 tinuous above with the keel of the ear-conch ; opposite this, on the 

 outer side of the concave surface of the conch, is a mushroom-shaped 

 process consisting of a short stalk supporting a broad flat reniform 

 expansion ; the outer margin of the conch terminates near the angle 

 of the mouth. 



Thumb with an ill-developed claw ; but the whole of the inferior 

 surface of its metacarpal and phalangeal bones supports a large flat 

 horseshoe-shaped pad, more than 0"'2 inch in diameter, of which 

 the circular margin is directed forwards and slightly notched in 

 front; this pad, though considerably larger "than that occupying 

 the same position in Thyroptera tricolor, does not form nearly so 

 perfect a clinging-organ as in that species ; for it is quite sessile, 

 without a trace of a peduncle, and its surface is flat, like the thumb- 

 pad of Vesperugo pachypus, with which it is evidently homologous. 

 The feet have also adhesive pads ; but, while resembling closely 

 those of the thumbs in structure and external form, they differ in 

 being much smaller, and so agree rather with those of Thyroptera 

 tricolor than with Vesperugo pachypus. 



The metacarpal bone of the index finger is well developed, being 

 nearly as long as that of the third finger, but there are no distinct 

 phalanges ; the third finger has three phalanges, of which the first 

 and second are nearly equal in length. 



The tail projects beyond the posterior margin of the interfemoral 

 membrane as in Thyroptera tricolor, but to a much greater extent, 

 the free portion being nearly equal to the tibia in length ; the 

 calcanea are almost as long as the tibiae ; the very narrow post- 

 calcaneal lobe is notched or toothed near the foot. 



As in Thyroptera tricolor, the toes are united as far as the base of 

 the claws, and have each two phalanges, and the wing-membrane 

 extends almost to the base of the claws. 



T\ j.1- T 2—2 1—1 3—3 3—3 



Dentition. — Inc. -7-, c. r^j, pm. g^, m. ^—^. 



Upper incisors short, in pairs, placed close to the canines ; the 

 outer incisor, on each side, small, conical, and acutely pointed, but 

 much larger than the inner one, which lies close to it and is hardly 

 visible without the aid of a lens ; lower incisors short and blunt, in 

 the direction of the jaws ; first and second upper premolars very 

 short, the third exceeding the molars in vertical extent ; second 

 lower premolar minute, in the tooth-row, the first premolar slightly 



