ON ARCTOCEBUS CALABARENSIS 611 
prostate is pyriform, broad above, narrow below, and has the 
ordinary structure. 
A “membranous portion” of the urethra unites the prostatic 
part with the slightly dilated bulbous portion and its continuation 
lodged in the corpus spongiosum. The bulb receives the ducts of 
the two large oval Cowper’s glands (Cf, figs. 11, 12), each of which 
has thick walls and a 
central cavity contin- 
uous with the ducts. 
The os penis, 0°75 
inch long, is situated 
between the corpora 
cavernosa, extending 
from the apex of the 
penis backwards in the 
middle line. 
The glans penis 
consists of a median, 
curved, subcylindrical 
portion supported by 
the extremity of the 
bone of the penis, and 
of a sort of hood, bifid 
below, which surrounds 
the base of this. The a as 
hood has a tuberculated The vasa deferentia, accessory generative glands and 
surface : and the urethra penis of the Angwantibo, dissected, and drawn of 
a 
‘\ ead 
\ vane gtk @. 
twice the natural size. A, viewed from behind ; 
opens between the lobes B, from in front, and slit open; «, 4, ¢, bristles 
introduced into the oval sac, vasa deferentia, and 
Cowper’s glands, respectively. In A: C. sf, the 
corpus spongiosum; 4, the prepuce; Ua, the 
urethral aperture. In B: Ur, the apertures of the 
ureters ; Pr’, of the prostate ducts ; UVa’, the urethral 
formed by its inferior bi- 
furcation, and therefore 
at some distance behind 
the apex of the organ. 
According to Van canal. 
der Hoeven’s account 
(1 ¢. p. 54), the male reproductive organs of the Potto must be very 
similar to those of the Angwdntibo ; and Kingma’s description and 
figures demonstrate the like for Otolicnus peli. Kingma, in fact, has 
worked out the anatomy of the parts more thoroughly than Van 
der Hoeven; for he shows that, as in the Angwantibo, the hollow 
vesicles connected with the prostate open independently of it and 
of the vasa deferentia, and does not admit them to be vesiculz semi- 
nales. But it is unsafe to come to a conclusion respecting the nature 
of these parts without some knowledge of their development. 
