200 Messrs. Hancock and Embleton on the Anatomy o/Eolis. 



ramifications as they are termed of the gastric cavity, which are 

 prolonged into the papillae. It cannot however be contended 

 that the chyle is transuded through the granular or glandular 

 part, such as occurs in many of the Eolidida in the papillae, 

 since it is manifestly a secreting and not an absorbing surface, 

 and the current must set from without inwards. Now in E. de- 

 specta the central duct or stem, and its accessory ducts, as well 

 as their terminations in the papillae, are granular throughout; 

 therefore the fact of the whole apparatus being one for secretion 

 precludes the idea that the products of digestion can pass into 

 the system from this organ. This arrangement we see in a still 

 more striking manner in several others of the Eolididce, as in 

 Hermcsa dendriticaj in which all parts of the much-branched 

 hepatic organ are alike granular. In Eumenis marmorata, in 

 which they are even follicular throughout, and in Dendronotus 

 arbor escens^f the central duct is crowded with compound follicles, 

 and all the branches are more or less follicular for a short di- 

 stance, and then become simply granular ; indeed in this genus 

 the posterior part of the stomach and the intestine are the only 

 parts which are free from the above granular character. We are 

 therefore led to conclude that it is from the pyloric end of the 

 stomach and from the intestine that exudation or ^sorption of 

 the chyle takes place, and this conclusion is strengthened by the 

 fact, that it is in the intestine that the contents first assume their 

 faecal character. We may add also that in Doto, the intestine, 

 which is short and wide, is in the interior longitudinally plicated, 

 as if thus to increase the extent of the absorbing surface. 



In conclusion then we hope to have shown, that not in any 

 of the systems of organs is Eolis notably below the Nudi- 

 branchiate type ; and we trust that this memoir, if it serve no 

 other purpose, will at least assist in rescuing this genus, and 



* In this genus we see an iiiterinediate link between those members of 

 the Nudibranchiata which are provided with a concentrated internal hepatic 

 organ and the EoUdidcB, a fact which we pointed ont two years ago. The 

 central duct is in fact nothing else than a true liver reduced somewhat in 

 bulk, but being diffused by its prolongations into the branchial papillae. 

 Another intermediate form and still more interesting link between the two 

 extremes, as it exhibits the fii'st step in the deviation of the liver from the 

 typical state, is seen in Scyllcea, and which we noticed in a paper communi- 

 cated to the Oxford meeting of the British Association. The liver in Scyllcea 

 is broken up into several globular masses of convoluted tubes sending off 

 minute branches that ramify in the skin and penetrate the branchial tufts. 

 In a paper by M. E. Blanchard in the ' Annales des Sciences Naturelles ' for 

 March 1848, we observe that that gentleman has discovered in Telhys a 

 similar arrangement of parts, and points this out as an excellent intermediate 

 illustration of the affinities that exist among the different members of the 

 Nudibranchiate group, and we are happy thus to find in his researches a 

 corroboration of the fact which we had prcviovisly cited for the same end. 



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