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BULLETIN 57, 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 ( =M ymctcops) 
was compared to Emballonura. It was next regarded as a member 
of the ‘ N octilionina ’ by Tomes, who afterwards placed it in the Phyl- 
lostomidse. Subsequently it was replaced among the ‘Noctilionidee ’ 
by Gray, who united it with the genus Noctilio to form the subfamily 
c Noctilionina.’ Dobson included it in the ‘ Emballonuridse ’ as a 
section ‘ Mystaeinse, 5 of the subfamily Molossinse, 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 Phyllostomidse. 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. S. Sulphur, Mammalia, Pt. 2, 
p. 23. Not Mystacinus Boie, 1822. 
1878. Mystacina Dobson, Catal. Chiropt. Brit. Mus., p. 442. 
1891. Mystacops Lydekker, in Flower and Lydekker, Mammals, living and 
extinct, p. (371. 
Type-species. — Mystacina tuberculata Gray. 
Geographic distribution. — New Zealand. 
Number of forms. — The type is the only species known. 
Characters . — Dental formula: 
-2-. 1. - 2-1567 .1-1 1-1 2-2 3-3 -J 
1 - 1. - 2-4 5 6 7 * 1-1’ c 1-1 ' pm 2-2’ m 3-3 -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 
