XII 



PHYLUM MOLLUSC A 



.) 



. > 



their posterior junction is given off a median diverticulum 

 (Fig. G7l,med.s), into which the pancreatic follicles (pane.) project. 

 Through each excretory sac runs the corresponding afferent 

 branchial vein, formed by the bifurcation of the vena cava, 

 and surrounding it are masses of glandular tissue (Fig. 67o| 

 ven. app\ by whose agency the process of renal excretion (the 

 products of which, in the shape of a nitrogenous excretory 



v.cav 



Fir;. f>70. Sepia officinalis, excretory organs. aM. <'. abdominal vein ; a/ii, funnel-like opening 



and Jung, after Grobben.) 



substance called guanin, are to be detected in the internal cavity) 

 is carried on. 



Reproductive system. In the male the test-is (Fig. 672, tc.) 

 forms a compact mass of minute tubules situated in the aboral 

 region of the body and enclosed in a capsule. The single spermi- 

 duct (v. def) is a greatly convoluted tube which leads from the 

 cavity of the capsule towards the right ; it opens into an elon- 

 gated vesicula seminalis (ves.), to which is appended a glandular 

 body, the prostate (pr.). In the interior of the vesicula seminalis 



