63 



and passing off in the vessel on its inner side, is carried 

 back by a vein to the lateral vena cava (fig. 63, Br. gld. 

 V.). This it enters just external to the branchial heart. 

 Probably this gland is connected with the manufacture 

 of the corpuscles of the blood of Eledone and other 

 ( Vphalopods. 



2. Skin. — As the skin of Eledone is very plentifully 

 supplied with capillaries; especially from the venous 

 system (figs. 57 and 58), it is possible that there is also a 

 ceil a in amount of cutaneous respiration. 



COELOM. 



All Molluscs have a reduced eoelom, and a corre- 

 spondingly dilated haemocoel. Although this pheno- 

 menon of " phleboedesis " has not been carried so far as 

 in the Arthropoda, still (1) the eoelom has ceased to be 

 a true perivisceral cavity and its main remnants are the 

 pericardium and the genital cavity, which still communi- 

 cate with one another ; and (2) large venous sinuses occur, 

 forming a secondary body cavity. 



Whereas in Sepia the pericardium and genital 

 cavity are both well developed, and are only separated 

 from one another by an incomplete dorsal septum, in 

 Eledone and other Octopoda the pericardial division is 

 greatly modified and reduced. It is represented by a pair 

 of thin-walled, semi-transparent, flask-shaped pouches 

 (PI. V, fig. 40, Cod.), situated laterally, dorsal and 

 posterior to the base of the ureters. Posteriorly each pouch 

 contains the corresponding branchial-heart-appendage, 

 or pericardial gland (fig. 40, Br. app.), while anteriorly 

 it opens into the corresponding ureter, by an oval reno- 

 pericardial aperture in the dorsal wall (fig. 40, R. Pe. ap.). 

 The genital division of the eoelom is well developed in 



