PHYTIVOROUS MOLLUSCA, 



333 



The system is found fully developed only in the Eolida^. 

 In these delicate and beautiful Nudibranches the short oeso- 

 phagus leads into a comparatively large pear-shaped sto- 

 mach ; and from the upper surface of its posterior extremity 

 a short intestine proceeds, which, after a slightly tortuous 

 course, terminates anteriorly, on the right side of the body, 

 in a small nipple-like vent. But, besides this intestine, 

 another chylous vessel is continued from the stomach, in 

 the form of a wide tapering canal, along the median line, 

 and terminates near the posterior extremity of the body 

 in a blind sac. From the stomach itself, as well as from 

 its continuation, branches are given off in pairs, not, how- 

 ever, in perfect symmetrical order, but always more or less 

 alternating. These branches give off smaller tubes, which 

 are continued into the branchial papillae, and lined with 

 a follicular apparatus for the biliary secretion. The en- 

 closed figures (Fig. 67), copied from the engravings of 



Fig. 67. 



Messrs. Hancock and Embleton, will give you a correct 

 idea of what I have attempted too shortly to describe;* 



* On the Anatomy of Eolis, in Ann. and Mag. N. Hist. xv. p. i., and 77. 

 See also Ann. and Mag. N. Hist. xii. 236 ; and AUman on the Anatomy 

 of Actseon, in vol. xvi. 14G. 



