240 BULLETIN 51, UNITED STATES NATIONAL MUSEUM. 



truncate, with rudimentary nostril pad, and with a sprinkling of 

 stiffened hairs, these, however, without spoon-shaped tips; wing not 

 narrowed, of the usual Vespertilionine proportions; the fifth finger 

 much longer than metacarpal of third ; claws on thumb and toes with 

 supplementary basal talon ; membrances thick and leathery, the uro- 

 patagium narrow, the short tail projecting from near middle of its 

 upper surface. 



History. — When first described the genus Mystacina (=Mystacops) 

 was compared to Emballonu.ra. It was next regarded as a member 

 of the l Noctilionina ' by Tomes, who afterwards placed it in the Phyl- 

 lostomid*. Subsequently it Avas replaced among the 'Noctilionidse ' 

 by Gray, who united it with the genus Noctilio to form the subfamily 

 ! Noctilionina.' Dobson included it in the ' Emballonuridse ' as a 

 section ' Mystacina?,' of the subfamily Molossinae, a position which it 

 has retained, essentially unmodified, in subsequent works. 



Remarks. — In the structure of the shoulder joint and in the broad 

 wing this family is less modified than the Molossidse. The palatal 

 branches of the premaxillaries are larger and more distinct than in 

 those genera of Molossidse in which they are present, this character, 

 together with the ossified third phalanx of the middle finger, suggest- 

 ing the Phyllostomicla?. On the other hand, a high degree of special- 

 ization is indicated by the perfectly Molossine leg and foot and by the 

 very remarkable secondary talons of the claws. 



Principal subdivisions. — The family Mystacopidse is represented by 

 one genus only. 



Genus MYSTACOPS Lydekker. 



1843. Mystacina Gray, Voyage of H. M. U. Sulphur, Mammalia, Pt. 2, 



p. 23. Not Mystaciniis Boie, 1822. 

 1878. Mystacina Dobson, Catal. Chiropt Brit. Mus., p. 442. 

 1891. Mystacups Lydekker, in Flower and Lydekker, Mammals, living and 



extinct, p. G71. 



Type-species. — Mystacina tuberculata Gray. 

 Geographic distribution. — New Zealand. 

 N umber of forms. — The type is the only species known. 

 Characters. — Dental formula : 



-2-. 1. -2-4567 .1-1 1-J _2-_2 3-3 

 1--. 1. -2-4567* 1-1' c 1-1' P m 2-2' m d^d~ 28 - 



Upper incisors more than half as large as canines, their crowns 

 oblique, noticeably separated below, in contact at about middle, 

 diverging at tip, the anterior surface convex, the posterior concave, 

 with faintly indicated basal cusp; laterally they are separated from 

 canines by narrow but evident spaces. Lower incisors well developed, 

 functional, closely crowded between canines, their cutting edges evenly' 

 and deeply trifid, their crowns so extended backward that their width 



