VESPERTILIONIDA 665 
these the best-known, J. schreibersi, is very widely distributed, being 
found almost everywhere throughout the tropical and warmer 
temperate regions of the eastern hemisphere; specimens from 
Germany, Madagascar, Japan, and Australia differing in no 
appreciable respect from one another. 
The last or Thyropterine division, which likewise comprises only 
two genera, is characterised by the presence of an additional osseous 
phalanx in the middle finger and an equal number of phalanges in 
the toes, and also by peculiar accessory clinging organs attached 
to the extremities. 
Thyropteru..Dentition : i 2, ¢ 1, p 8, m3; total 38. In the 
single species YT. tricolor of Brazil the clinging organs have the 
appearance of small, circular, pedunculated, hollow discs (Fig. 311), 
resembling in miniature the sucking cups of cuttle-fishes, and are 
Fic. 311.—Suctorial discs in Thyroptera tricolor. a, Side and }, concave surface, of thumb- 
dise ; c, foot with disc, and calear with projections (all much enlarged). Dobson, Proc. Zool. 
Soc. 1876. 
attached to the inferior surfaces of the thumbs and soles of the 
feet. With these the animal is enabled to maintain its hold when 
creeping over smooth vertical surfaces. 
Muyxopoda.2—The second genus is likewise represented only by 
a single species—AJf. aurita of Madagascar—and is distinguished 
from the preceding by the characters of the teeth and the form of 
the ears. The whole inferior surface of the pollex supports a 
large sessile horse-shoe-shaped adhesive pad, with the circular 
margin directed forwards and notched along its edge, and a 
smaller pad occupies part of the sole of the foot. 
Fossil Vespertilionidee.—It is not improbable that lesperugo is 
represented in the Upper Eocene of the Paris basin by J” pavi- 
siensis, which appears to be allied to 7”. serotinu, although it has 
been regarded by some writers as generically distinct, under the 
name of Nyctitherium.  Tesperugo (Nyctitherium) also occurs in the 
Bridger Eocene of the United States; Nyctilesies from the same 
1 Spix, Sim. and Vesp. Bresil, p. 61 (1828). 
2 A. Milne-Edwards, Bull. Soc. Philom. sér. 7, vol. ii. p. 1 (1878). 
