On the Genera Cyclostoma and Pomatlas. 447 



XLVIII. — The Genera Cjclostoma and Pomatia=?, and on a 

 misapplied rule of Zoological Nomenclature. By the Rev. 

 Canon A. M. NoRMAN. 



Alarmed, on reading Mr. E-. B. Newton's paper in last 

 month's ' Annals,' at the prospect of having to give up the 

 titles of the above genera, so long familiar to me, and at that 

 of having to change the names of about one hundred and 

 twenty " species " in my collection, I at once was led to look 

 into the matter in order to discover how it was that concholo- 

 gists for the last ninety years had been ignorant of what 

 they were about. 



The result is '^ that it seems clear that Mr. Newton hafj 

 misapprehended the facts, and that no need exists for changing 

 the names Cyclostoma and Pomatias as now in use. 



The year 1799 is not the same as 1891, and our ideas of 

 genera are very different from those then in vogue. In 

 the last century genera were very few, now we are groaning 

 under the weight of far too many. Has not Mr. Newton 

 fallen into the mistake of supposing that Lamarck formed 

 three genera named Cyclostoma^ whereas he only formed 

 one, but employed that name with different applications? 

 Again, Draparnaud established no new genus ; he simply 

 excluded the marine shells which fell under the characters 

 of Lamarck's Cyclostoma (which genus, as first defined 

 by Lamarck, was designed to include every genus to which 

 Mr. Newton refei'S in his paper), and restricted its use to 

 the round and entire-mouthed land and freshwater species. 



Lamarck himself and his editor Deshayes shall testify to 

 facts out of the last edition of Lamarck, which I am led to 

 suppose Mr. Newton did not consult. It must be borne in 

 mind that in this and the previous edition species of Cyclo- 

 stoma, Lamarck, 1799, are distributed in the three genera 

 iScalaria, Delphinula, and Cyclostoma. 



Under Scalaria Lamarck writes : — " Les Scalaires, qu'on 

 nomme aussi vulgairement Scalata, sont des coquillages 

 marins ti^s distinguds des Cyclostomes, non-seulement par la 

 habitation, et leur forme subterricul^c &c." 



Under Delphinula he writes : — " Ces coquilles se rap- 



prochcnt evidemmcnt des Scalaires par leurs ra[)ports 



Ces coquilles marines sont fort differentes, par leur epais- 

 seur, leur soliditd, I'etat de leur surface externe, des coquilles 

 terrestres que nous nommons Cyclostomes, quoique, de part 



♦ Though I have not the opportunity of referring to the earlier, but 

 only to the la«t two editions oi Lamarck. 



