OF CONCHOLOGY. 



203 



To use Helix for all Helicoid species collectively, as is done 

 now by many even eminent authors, is quite inadmissible by the 

 rules of scientific nomenclature, even when the vast group thus 

 included is divided into numerous subgenera. These should pro- 

 perly be called genera, at least in most cases, even when the 

 differences depend only on characters of the shells. 



If some one having the authorities at command will publish a 

 table of all the generic names ever given to them, with the date 

 of each, and name of first species, or of any other specified as 

 type, it is probable that nearly all may yet become of use in 

 making classifications or arranging cabinets. Our species cer- 

 tainly do not belong to Helix, and it is necessary to use some 

 other generic names for them. For Aglaia (thrice preoccupied) 

 H. and A. Adams use Lysinoe, of which the type seems to be L. 

 G-hiesbreghti, Nyst, of Mexico, very much like fiddis. 



Arionta (arbustorum), though differing from the nearest allied 

 of our species in its contracted mouth and want of rough sculp- 

 ture, is near enough to be used for them until distinctions are 

 found in the animals. 



At the time of writing the Synopsis of West Coast Helicoid 

 Land Shells, I had not seen Morch's articles in the Journal de 

 Conchyliologie for 1865. ^Mr. Bland has called my attention to 

 them, and I find that my mode of grouping the species is con- 

 firmed by that eminent autliority, whose remarks I quote as 

 briefly as is consistent with the nature of the subject : 



" 1st. The form of the lip is important chiefly as a generic 

 character. The teeth are specific only (but form good subgenera 

 among American species). 



" 2d. The umbilicus, very variable according to the shell's age, 

 has scarcely even a specific value. 



" 3d. The color, number, and position of the bands have, con- 

 trary to all expectation, a systematic and generic value of the 

 first rank, being always in relation with the form of the jaws and 

 darts."* 



then says that Lamarck's first Planorhis is an AmpuUaria^ apparently 

 forgetting that Guettard founded the genus before Linnaeus, who merged 

 it in Helix. This, therefore, does not prevent us from adopting the first 

 terrestrial Helix of Linn, as the type, whether given in the 12th Ed or 

 previously. Unfortunately I cannot refer either to his Museum Ulricse 

 or to Hanley's Linn. Conch., which may clear it up. Even his first writ- 

 ings in which the name Helix occurs may have to be consulted to settle 

 the point. 



*Morch finds the angled, umbilicated Chilotrema lapicida alosaly aXliQdt. 

 to the 3 — 4-banded, sometimes hirsute and angled group of Campylcea 

 cingulata, trigona, setosa, etc., which seem very like onr Aug uispir a? 

 solitaria, Coopers, and strigosa. "jLap^'c^'rfrt. sometimes has four bands 

 like its allies." It is not very distantly related to A. arbustorum, but 

 less nearly to Hygromia rufescens, &c. 



