CEPHALOPODA. 



453 



(496.) In the "great venous cavities" or "pericardium" thus 

 formed, are lodged the principal venous trunks (fig. 211, rf, d), 

 whereunto the blood derived from all parts of the body is brought 

 by capacious vessels (6, c, c) that may be called the vena cavte. 

 The great central receptacles of the venous blood (d, d), whilst 

 they are contained in the pericardium, (or rather project into its 

 interior, being partially covered with the mucous membrane that 

 lines its walls,) are enveloped by a mass of spongy appendages of 

 a most remarkable and peculiar description. These spongy masses 



Fig. 211. 



