13. NYCTiNOMirs, 435 



few hairs form a fringe along the anterior margin of the upper lip 

 beneath the nostrils. With the exception of a narrow band of very 

 short fine hairs, which extends on the upper surface of the wing- 

 membrane behind the forearm to the carpus, the membranes ex- 

 ternal to the humerus appear to be quite naked ; along the sides of 

 the body the fur extends as far outwards, above and beneath, as a 

 line drawn from the middle of the humerus to the knee. 



Upper incisors separated by a space in front ; lower incisors four, 

 biSd, crowded ; internal basal cusp of canine small ; first upper 

 premolar small, conical, acutely pointed, in the centre of the rather 

 wide space between the canine and second premolar ; second upper 

 premolar with an acute internal basal cusp ; first lower premolar 

 not crowded, as broad at the base as the second, which exceeds it 

 (as in all other species of the genus) in vertical extent. 



Length (of an adult (5, the type), head and body 3", tail 2"-l, 

 tail free from membrane 1""1, head 1"-15, ear 1", tragus 0"'15x 

 0"-l, forearm 2"-3o, thumb 0"-35 ; third finger — metacarp. 2"-25, 

 1st ph. 0""95, 2nd ph. 1""1 ; fourth finger — metacarp. 2"-l, Ist ph. 

 0"-8, 2nd ph. 0"-l ; fifth finger— metacarp. 1"-1, 1st ph. 0"-75, 2nd 

 ph. 0"-2; tibia 0"-7, foot 0"-45. 



Rab. Surinam. 



a. (S ad., al. (type). Surinam. 



16. Wyctinomus macrotis. 



Nyctinomus macrotis, Gray, Ann. Nat. Hist. iv. p. 5 (1839) ; Dubson, 



P. Z. S. 1876, p. 729, fig. 6. 

 Dysopes am-itus, Na t., Waf/ner, Wiegm. ArcJiio, 1843, p. 368 ; 



Burmeister, Thieve Brasiliens, p. 69 (1864). 

 Dysopes laticaudatus et cgbcus, Rengger, Sdugeth. Paraguay, p. 88. 

 ? Dysopes aurispinosis, Peale, United States Explor. Exyed. viii. p. 21 



(1844). 

 Nyctinomus auritus, Peters, MB. Alcad. Berl. 1865, p. 573. 



Ears large, nearly as long as the head, conjoined to a height of 

 0"'2 inch, the inner margins very convex, and consequently close 

 together for more' than half their length above the band uniting 

 their bases ; integument forming the ear-conch very 'thin, trans- 

 lucent ; keel very deep, projecting outwards beyond the antitragus, 

 but also very slender, curved backwards and upwards ; tragus small, 

 quadrate, superior margin straight or very slightly concave, upper 

 half of outer margin concave, lower half forming a prominent 

 angular projection ; antitragus considerably longer than high, ter- 

 minating in front between the eye and the angle of the mouth, 

 separated posteriorly by a deep notch (Plate XXII. fig. 6). Pace 

 deeply grooved horizontally beneath the eye, which is remarkably 

 prominent and directed forwards. Muzzle slender, concave between 

 the ears and the projectmg sharply cut superior margins of the 

 nostrils ; nasal apertures directed almost laterally, separated by a 

 wide space, which is divided in the middle by a raised vertical ridge. 

 Upper lip deeply furrowed by oblique wrinkles. No gular sac. 



