672 ANATOMY OF VERTEBRATES. 



and converge to unite, at the symphysis pubis, in a strong 

 common tendon, which passes over the ( vena dorsalis penis.' 

 Two slender fasciculi derived from the i retractor ani ' pass along 

 the bulb and under side of the urethra to the line of reflection of 

 the prepuce, where they are lost in the skin of the glans : they 

 bend back that part, in the unerect state, and cause the felines to 

 be ' retromingent.' 



§ 380. In Quadrumana. — The testes of the Aye-aye ( Chiromys) 

 occupy a sessile scrotum : the tunica vaginalis communicates with 

 the peritoneal cavity, but by too contracted a canal to permit any 

 return there of the testes, offering a notable difference from 

 Rodents. There are no vesicular glands ; but a moderate sized 

 compact prostate, and a pair of flattened oval Cowperian glands, 

 the ducts of which penetrate the urethral bulb. Besides the 

 i erectores ' and i acceleratores,' there is a pair of strong ' levatores 

 penis ' arising from a fascia below the symphysis pubis, crossing 

 the vena dorsalis, and inserted by a common tendon into an 

 'ossiculum penis.' The penis, of a subcorneal form, projects 

 about an inch, in the unerect state, it is covered by the thin 

 naked skin of the prepuce, which has a transverse orifice. 



In the Slow Lemurs (Stenops Tarsius, Otolicnus, Perodicticus) 

 there are vesicular glands in the form of oval subcompressed bags, 

 with a plicate or honeycombed inner surface: their ducts terminate 

 distinctly from those of the testes. The prostate has a bifid base 

 and compact structure. The Cowperian glands are relatively 

 large. The short penis has an ossicle, and projects, or hangs 

 conspicuously as in Chiromys: the ossicle ends in a terminal 

 process of the glans. 1 In the Makis (Lemur) the vesicular 

 glands consist each of an elongate caecal tube, bent inward 

 and downward at their free end, with thin walls and a minutely 

 rugous inner surface : in other respects the male organs resemble 

 those of Chiromys. Each * levator penis ' arises from the upper 

 part of the crus : they converge above the two ' venae dorsales ' 

 to a common tendon which runs along the dorsum penis to the 

 ossicle. The glans is large and expands to a free truncate end 

 with the urethra opening near the centre of the disc ; the sides 

 of the glans are beset with small callous papillae. 



The scrotum is more pendent in Platyrhine and higher 

 Quadrumana : the vesicular glands have thicker parietes and a 

 more lobulated or ramified form : the prostate is more compact : 

 the Cowperian glands become reduced in size. The penis is 

 prominent or pendulous in all. The glans terminates by a 

 large expansion in Ateles. In Cebus capucinus Cuvier found no 



1 xx. vol. iv. p. 101. 



