510 THE NATURAL HISTORY REVIEW. 



- How can one be sure, in comparing one description with another, 

 how far they differ, and how far they agree, unless there be a fixed 

 and definite nomenclature. Some years ago, in 1856, Professor 

 Huxley attempted to introduce, among the Annelida, a modification of 

 the system of nomenclature, proposed with so much success by Milne- 

 Edwards, among the Crustacea. But this system has not been adopted 

 as it ought to have been, and even in the latest works on the Annelids, 

 and in the very last papers descriptive of new species, we find the 

 same old, we wish we could say antiquated, terms introduced. Every 

 Annelid is composed of a certain number of somites ; one or more of 

 these may also form a segment ; the cephalic segment may consist of 

 several somites, and is conveniently called by Professor Huxley the 

 peristomium, the terminal segments, the pygidium ; but each somite, 

 as a general rule, has a certain number of appendages : these, Pro- 

 fessor Huxley calls parapodia — each parapodium divides into two 

 portions, a notopodium and neuropodium. Now, it strikes us, if 

 this nomenclature had been attended to, and enlarged as occasion 

 required, our knowledge of the external anatomy of the Annelids 

 would have been much more clear and exact. We call attention to 

 this subject here, in the hope that future writers on this group of 

 animals may be induced to abandon the old style and adopt the 

 new. 



Polio wing Grube, Dr. Johnston divides the Annelida into the 

 Bapacia and Limivora, corresponding to tke Errantia and Seden- 

 taria of Milne-Edwards. As a Zoological convenience this division 

 may be accepted for a short time longer ; but there is no very sharp 

 line of distinction to be drawn between the animals of either 

 group. In the arrangement of the families and genera, Grube is 

 not followed very explicitly. Taking Cams' s arrangement of the 

 families as a recent guide, we will see what genera and species are met 

 with in this country. Of the Aphroditea, we have the genera Aphro- 

 dita (3 species), Lepidonotus (8 species), Folynoe (1 species), Pliol'de 

 (2 species), and Sigalion (1 species) ; of the Aphinomea, Euphrosyne 

 (2 species), Spinther (1 species). There is no diagnosis of this latter 

 genus given in the text, nor is the omission alluded to in the appendix. 

 This is the more to be regretted as the original description in the 

 Annals and Magazine of Natural History was, necessarily, very in- 

 complete. 



Of the Eunicea, we have Eunice (7 species), Onuphis (2 species). 

 Dr, Johnston divides Audouin and Milne-Edwards' genus Onuphis 



