THE NAUTILUS. 143 



also collected by Mr. Singley) the same three were represented, but 

 procera in small number. Among about 60 specimens from Hidalgo, 

 Texas, (Mr. Singley, coll., sent by Mr. Wm. A. Marsh) there were P. 

 hordeacella, hordeacea in a form somewhat differing from the type, 

 and the species mentioned above ; P. procera wanting. 



From New Mexico I have seen P. hordeacea and hordeacella. 

 Texas seems to be the center of distribution of the group under con- 

 sideration on our continent, and there is no doubt but that more 

 valuable things will be .found in that .state and the neighboring 

 territories. 



My own collection now contains about 65 numbers (75 vials) of 

 the forms named above (except P. servilis) from the continent, and 

 many more I have seen in other collections. 



The title of this article may appear to be not fully appro- 

 priate, in so far as the species named there is the one, or one of the 

 furthest removed from the common type of the whole group. Yet 

 P. rupicola Say is the oldest and best known name, and, I think, 

 the choice of it may be justified. 



[CONTRII'.I'TED.] 



AMERICAN ASSOCIATION OF CONCHOLOGISTS. 



Santa Barbara, Cal., Feb. 3, 1891. 

 To the President of the American Association of Conchologists : 

 Dear Sir : 



In response to your circular card of November 7, notwithstanding 

 the probability that you may consider my response as coming too 

 late, I venture to make a few remarks : 



I regret to see the evident tendency among conchologists who are 

 coming into print, to make radical and uncalled for changes in no- 

 menclature. 



I have noted more particularly those relating to our West Coast 

 shells. 



We, who have been for the past twenty-five or thirty years, ac- 

 customed to the names by which our mollusks have been known, 

 fail to see the necessity or utility of making so many changes, espec- 

 ially by those not resident, nor esjjecially interested in our local con- 

 chology, which renders our standard publications next to useless, 

 places difficulties in the way of young students, puzzle and annoy 

 our older naturalists, and have a tendency to fence in the field of 



