THK NAUTILUS. 39 



the (^height of the) whorl, and l)y the wanting constriction, e.-rpecially 

 in the coluniellar wall, not to speak of the size and shape of the whole 

 shell. The laraelhe also show some marked differences, such as the 

 presence of a high basal, the shorter coluniellar not reaching the 

 base, but with relatively larger horizontal i)art, the bifurcatit)n of the 

 parietal and the presence of a supra-palatal, the last just as it is in 

 P. armifera. 



It must be added here that the specimen first obtiiined from 

 Minnesota in several respects differs from those found in Illinois and 

 Iowa, which I consider as typical ; by its size which is h smaller, by 

 the basal lamella developed in a peculiar way, being rather longer 

 at the truncated top than at its foot, and by the stronger, thicker 

 palatal lamellse. Yet, as there was only one specimen, it was lial)le 

 to be an individual peculiarity — even then of interest. Should, 

 however, more specimens be found with the same configuration, they 

 would represent a distinct and well characterized variety ; possibly 

 it is a peculiar northern form. 



New Philadelphia, Ohio, June, 1889. 



ON MR. PILSBRY'S CRITICS UPON SOME AMERICAN SHELLS. 



BY C. F. ANCEY. 



In the 9th No. of the Con cholo gists' Exchange, Vol. II, 1888, p. 

 113, Mr. H. A. Pilsbry wrote: "On Lyogyrus, Gill, and other 

 American shells," in which several subgeneric and specific names 

 proposed by European scientists for N. American shells, particularly 

 by Dr. Westerlund and myself are sharply criticised. Of course 

 criticism is good whenever errors generally diffused are to be 

 destroyed, and when not inconsiderate. I intended, at first, to write 

 about this subject in "Le Xaturaliste," where " some of Mr. Crosse's 

 genera are so rudely handled," but I at length determined to insert 

 my article in the same paper as that in which Mr. Pilsbry published 

 his own note, in order to be read by the same naturalists. 



It will be remarked at first, that before speaking about the new 

 species proposed by such a man as Dr. Westerlund, an eminent 

 conchologist, and certainly, together with Dr. W. H. Dall, the one 

 who is the best acquainted with the conchological fauna of the Arctic 

 countries, it would be well to compare either his shells with authen- 

 tic specimens of those formerly described, or his very accurate 



