THE MALE GENEBATIVE OBGANS 103 



muscular coat of longitudinal and circular fibres, and is lined 

 with cylinder epithelium. 



The ejaculatory organ (Plate IX., 13) is a peculiar chitinous 

 capsule, surrounded by a mass of muscles between the vas 

 deferens and ejaculatory duct. It is about 1-1 00th of an inch 

 in length in its longest diameter. It consists of a cup-shaped 

 cavity, the capsule, from the smaller extremity of which a 

 strong chitinous tube, the manubrium, projects. The manu- 

 brium terminates in a curved knob, which is perforated on its 

 convex side by six or eight small apertures, and marked by 

 two strong lateral ridges. These ridges are continuous with 

 a membranous sac, which forms the inner extremity of 

 the ejaculatory duct. The sac communicates with the in- 

 terior of the knob by the perforations on its convex side. 



The vas deferens perforates the manubrium near its junction 

 with the capsule. The capsule is closed at its larger extremity, 

 and numerous bands of muscle which surround the whole organ 

 arise from the concave surface and edges of the knob-shaped 

 end of the manubrium, and are inserted into the edges of the 

 capsule close to its large extremity. 



The ejaculatory duct is membranous, and not more than 

 l-1000th an inch in diameter ; it is about l-15th of an inch in 

 length from its commencement at the ejaculatory organ to its 

 termination at the end of the penis. The vas deferens, when 

 examined immediately after it ig removed, may be observed in 

 a state of vigorous peristaltic action, by means of which the 

 male fluid is, doubtless, conveyed to the ejaculatory organ. I 

 have not been able to satisfy myself as to the existence of a 

 muscular coat to the testes, but from the varieties of hour-glass 

 contraction they exhibit, and the large supply of nerves which 

 they receive from both senso-motor and sympathetic systems, 



