240 



COMPARATIVE ANATOMY 



CHAP. 



vesicula seminalis opens into the large prostata near the point where the latter enters 

 the spermatophoral pouch. This point lies, not in the base, but in the neck of the 

 pouch, where the latter is produced into the long fleshy penis, the point of 

 which projects into the mantle cavity. The penis is provided with a lateral 

 csecum. 



It has already been mentioned that, as far as we know at present, only two living 



ventral. 



SfT. 



dorsal. 



Fio." 198. Female genital organs ol Sepia officinalis (chiefly after Brock). The mantle 

 cavity is opened, the posterior integument of the visceral dome removed, the ink-bag laid some- 

 what to one side, and the oviduct uncovered. The complex of organs thus exposed is seen from 

 behind. 1, Funnel ; 2, edge of the aperture of the funnel ; 3, cartilaginous locking apparatus ; 

 4, left ganglion stellare ; 5, glandular terminal portion of the oviduct with the female genital 

 aperture ; 6, left lateral lobe of the accessory nidamental gland ; 7, gland of the oviduct ; S, left 

 gill ; 9, oviduct filled with eggs which are seen through its wall ; 10, left nidamental gland ; 11, 

 mantle ; 12, ovarial sac, opened from behind, the stalked ovarial eggs are seen on its anterior wall ; 

 13, ink-bag (pigment gland) ; 14, stomach ; 15, right nidamental gland ; 10, central portion of the 

 accessory nidamental gland ; 17, right lateral lobe of the same ; 18, right gill ; 19, right renal 

 aperture ; 20, anus. 



Cephalopods, Nautilus and Philonexis carcnce, have paired male ducts. In 

 the left duct is rudimentary. Whether the two ducts of Philonexis carence correspond 

 with the two ducts which we may assume that the Cephalopoda originally possessed 

 is very doubtful. The two vasa deferentia of Philonexis, which arise out of the 

 testicular capsule, and differ considerably in structure, unite together later, and 



