CHITON. 



CORPUS repens, oblongum, conveximi, extremK 

 tatibus rotimdatum, in ambitu cute coriacea 

 marginatum; testa octavalvi in serie unica, et 

 longitudinaliordinata, dorso incumbente: valvis 

 mobilibus, omnibus, vel plerisque imbrieatis, 

 plerumque transversis, laterum extreniitatibus 

 cutis margine replicato connexis. 



Though in order to describe tlie peculiar cliaracters of 

 such a genus as the present, we certainly have no occa- 

 sion for a knowledge of the animal; yet if we would 

 ascertain with precision, its proper place in the concho- 

 logical system, the shell itself is so singular, that a refer- 

 ence to the characters of the animal is absolutely impera- 

 tive. In most cases an attainment of this knowledge is 

 attended with great difficulties, but in the present this is 

 not the case, because being composed of several pieces, at 

 least a portion of the animal must be preserved to keep 

 the valves together, consequently the nature of this animal 

 is better known than that of many others ; from an exa- 

 mination of its structure, Lamarck concludes, that the 

 Chiton (as well as his Chitonellus) are very nearly related 

 to the Patellce, and intermediate between his Phyllidiccy 

 (moUuscae without any shell, whose back is covered with 

 a coriaceous skin) and Patella: although the accurate and 

 learned Cuvier, whose anatomical researches have cour- 

 tributed so largely to the advancement of conchological 

 science, and who has examined all the above-named ge- 

 nera with great attention, does not discover so near a 

 resemblance between the Phyllidia and the Chiton, as he 

 does between the Chiton and Patella. The position of the 

 t)ranchia, surrounding the body beneath the mantle^ \^ 



