VESPERUGO. 21 
of the mandible. The only specimens yet known are the types, an adult and a young 
example, collected by Herr J. Sivers at Yzabal de Guatemala, and preserved in the 
Berlin Museum 1. : 
3. Vesperugo albigularis. (Tab. III. fig. 1.) 
Vesperus (Marsipolemus) albigularis, Peters, Monatsb. Ak. Berl. 1872, Pe 260 ‘(deser. orig.) °. 
Vesperugo albigularis, Dobson, Cat. Chir. Brit. Mus. p. 207°. 
Hab. Mexico (Mus. Berol.'). 
This curiously-coloured Bat differs from the rest of the genus in the manner in which 
the lower extremity of the outer margin of the ear-conch is produced forwards so as 
to form a sort of shallow pouch below the angle of the mouth; and Professor Peters 
has consequently instituted the subgenus Marsipolemus for its reception. Mr. Dobson 
considers it as indicating an approach to the genus Chalinolobus?. The only specimen 
yet recognized is the type in the Berlin Museum, an apparently adult male, stated to 
be from Mexico, but of which the exact locality has not been received; and I am 
indebted to the kindness of Professor Peters for the drawing from which our figure 
is taken. 
4. Vesperugo parvulus., (Tab. III. fig. 2.) 
Rhogoésa parvula, H. Allen, Proc. Acad. Philad. 1866, p. 285 (descr. orig.) *. 
Rhogoésa tumida, H. Allen, tom. cit. p. 286 (descr. orig.) *. 
Vesperugo parvulus, Dobson, Cat. Chir. Brit. Mus. p. 245 °. 
Hab. Mexico, Tres Marias (Grayson, U.S. Nat. Mus.'), Mirador (Sartorius, U.S. Nat. 
Mus.2); Honpuras (Dyson, Brit. Mus.*); Guatemaua, Vera Paz (Mus. Berol.); 
Costa Rica (Mus. Brit.’). 
This species differs from the rest of its congeners in having only two upper incisors 
and two upper premolars ; and Dr. H. Allen, recognizing two closely allied species, made 
them the types of a new genus, Rhogoésa, which he regarded as allied to the Noctilio- 
nide!2. Mr. Dobson, however, remarks that “although this species has the dental 
formula of Nycticejus, it, in all other respects, evidently belongs to the genus Vesperugo. 
This is especially shown by the notched upper incisors, the form of the ear and tragus, 
and the distinct postcalcaneal lobe.” He adds that he has little doubt of the identity 
of the two species described by Dr. Allen, 2. twmida being evidently described from a 
more full-grown specimen than the types of 2. parvula®. 
Our figure is from one of the Costa-Rican specimens in the British Museum, which 
also contains examples collected in Honduras by Mr. Dyson; others from Guatemala 
are preserved in the Berlin Museum. 
