Haduon — 0)1 Generative and Urinary Duds in Chitons. 235 



tions in an imperfect series of Ch. cinereus (Linn.), I feel confident 

 that it occurs in that form. And, lastly, I have seen it in Ch. 

 longicymba (De Blainv.). The latter is one of the species collected 

 by the " Challenger " Expedition. In my forthcoming Report on 

 the anatomy of the group, which will be published by the " Chal- 

 lenger " Commission, I hope to be able to elucidate this and other 

 points in the anatomy of this interesting group, by the examina- 

 tion of a larger range of forms than has as yet fallen to the lot 

 of any naturalist ; and till then I will not attempt any generaliza- 

 tions. 



In the foregoing Paper I have simply spoken of the species 

 referred to as belonging to the genus " Chiton." I now append 

 a list of the genera, adopting the nomenclature which is in most 

 general use: — 



