proposed rejection q/*Cyclostoma. 525 



should be changed which has before been proposed for some 

 other genus in zoology or botany, or for some other species 

 in the same genus, when still retained for such genus or 

 species." He advocates the application of the latter part of 

 this rule to the genera under consideration. He argues 

 that if the first Cychstoma is inadmissible, we must accept 

 the second, though I have distinctly proved it to be the 

 equivalent of Studer's genus of 1789. I beg therefore to 

 differ materially from the Rev. Canon when he intimates 

 that I have misapplied a rule of nomenclature in rejecting 

 Cyclostoma^ as I hold that 1 have not violated it in any one 

 particular. 



He appears to be only anxious to demonstrate that we 

 should follow the opinion most generally received by con- 

 chologists on this subject, instead of thinking it a matter for 

 congratulation that tiie discovery of the Studerian genus now 

 relieves us from the difficulties that have surrounded Cych- 

 stoma for upwards of ninety years. 



In considering the latter part of this tenth rule, however, I 

 can imagine grave difficulties arising in its application^ and I 

 beg to enter a very strong protest against it. 



There will always be a variety of opinions as to whether 

 an earlier name is obsolete or not. Rather than have this 

 liesitation in the matter let us erase this clause from our statute- 

 book and adopt the law of priority, without the particular limit 

 specified, as a "fundamental " maxim. ]f reference is made 

 to the American* view on this subject v/e find no such restric- 

 tion in force. Canon xxxiii. reads: — " A generic name is to be 

 changed which has been previously used tor some other genus 

 in the same kingdom." Again, Canon :^\\. contains, "The 

 adoption of a ' Statute of Limitation ' in modification of tlie 

 Jeic priovitatis is impracticable and inadmissible," Turning 

 to continental views, we find it stated in Dr. R. Blanchard's f 

 report, article xii., " Tout nom generique dc^ja employe dans 

 le meme Regne devra etre rejet^." ■ A number of other 

 instances could be quoted where we fail to discover the 

 irksome limit implied in our English rule in the exercise of 

 this law of priority. Suppose for a moment we consider 

 Rule 10 in its application to the cxamj)le given us by Canon 

 Norman, viz. the genus Normania. Thrice has this name 

 been applied. The first is rendered a synonym, because 



* ' Tho Codo 1)1" Nomenclature and CLeeli-List of North-American 

 IJiids, being- tlie Keport of the Connuittee of the Union of Clal^8ificatiou 

 and Nouienchiture. 8vo, New York, 1886. 



t ' l)e hi Nomenclature des Klrcs Oifranise.-^. Kappnil pro.-enle au 

 Congrcs Inlernatioual de Zookigie.' 8vo, Taris, 1880. 



