XII 



PHYLUM MOLLUSCA 



753 



of a spring for causing the rupture of the wall and the discharge 

 of the sperms. The vesicula seminalis expands into a wide sac 

 the spermatophoral sac or Needham's sac (Fig. 681, sp. s.) in the 

 interior of which the spermatophores are stored. This opens into 

 the mantle-cavity by the aperture already described at the extremity 

 of the penis to the left of the middle line. 



In the female the ovary (Fig. 667, ov.) occupies a position 

 corresponding to that of the testis in the male, and is enclosed in 



spr* 



Fia. 681. Sepia, reproductive organs of male. pn. penis ; 

 pr. prostate ; sp. s. sperm-sac ; te. testis ; v. def. vas 

 deferens ; res. vesicula seminalis. (After Keferstein.) 



FIG. 682. Sepia. A, sperms, 

 highly magnified ; B, sperma- 

 tophore. sp. mass of sperms ; 

 spr. spring apparatus by 

 which the wall of the sperma- 

 tophore is ruptured. (From 

 Vogt and Jung.) 



a similar capsule, with the cavity of which 

 the lumen of the oviduct is continuous. 

 An axial swelling bears numerous follicles, each containing a 

 single ovum supported on a long slender stalk ; the different ovaare 

 in various stages of development. At the breeding season the 

 ovary becomes a compact mass of ova, which assume a polygonal 

 shape owing to mutual pressure. The oviduct (ovid.) is a wide 

 tube, opening, as already described, into the mantle-cavity to the 

 left of the rectum. Occupying a conspicuous position on the anterior 

 wall of the mantle-cavity of the female is a pair of large flattened 

 glands of somewhat oval outline, the nidamental glands (nid), 

 situated to the right and left of the ink-duct. In the long axis of 

 each is a median canal, on either side of which is a range of closely- 



