PAPERS RKLATING TO NATURAL HISTORY. 187 



NOTICES OF PAPERS RELATING TO NATURAL HISTORY 

 RECENTLY RECEIVED. 



First in order we place a paper by Professor Morse, of Portland,, 

 on A Classification of Mollusca, Based on the Principle of Cephali- 

 zation, which appeared in the proceedings of the Essex Institute, Vol. 

 IV. 5 No. VI., and which has been in our hands for some time, but 

 which seemed to us of such importance that we were anxious to be- 

 stow upon it a fuller consideration than other occupations at the time 

 permitted ; and we reserved it with the intention of expressing at 

 large our views on the whole subject. We regret that this intention 

 must still remain unfulfilled ; but we will at least express our sense of 

 the knowledge, thought, and original research displayed in the paper,, 

 and give a short account of its purpose and character, with a few cri- 

 tical remarks. The author makes it a special object to determine the 

 common plan of the Molluscous sub-kingdom, which he regards as 

 still remaining in obscurity : — 



"Finding the universality of vertebra tion among the Vertebrata, of articula- 

 tion among the Articulata, and similarly of radiation among the Radiata, I 

 could not but believe that in the Mollusca some plan lay hidden, which, when 

 unfolded, would as definitely convey their type, and unite them all, as in the 

 other branches. It is not enough to call them soft bodied animals ; for in con- 

 sidering their shell as a part of their organization, vee have among them many 

 of the hardest animals known, and we also have an equal number of soft bodied 

 animals in the other branches. Their bilaterality, as expressing anything defi- 

 nite, is an equally unsatisfactory character. Prof Huxley has given an arche- 

 type, or common plan of the Mollusca, as he conceives it, with many truthful 

 homologies, in the article ' Mollusca,' English Cyclopedia, Vol. III., p. 885 In 

 his figure of the archetype, however, which is bilaterally symmetrical, we have 

 details of structure only." 



He adds : — 



"Prof. Dana has been the iii'st to publicly announce the plan of Mollusca, 

 when he says, ' The structure essentially a soft, fleshy bag, containing the sto- 

 mach and viscera, without a radiate structure, and without articulations.'" * 

 He then states that, 



" In the year 1862, Mr. Alpheus Hyatt had independently worked out a similar 

 result." 



Adding : — 



"Mr. Hyatt also proposes the name Saccata as more fully and truthfully ex- 

 pressing the type, than the unmeaning word Mollusca. This name not only ex- 



• Dana's Manual of Gcologj', p. 148. 



