HELIX. 83 



Say in the collection of the Philadelphia Academy. It 

 represents the only form of the species, those included by 

 Binney under the same name being referred more properly 

 to the succeeding species. There is consequently much 

 confusion in the synonymy, remarks, and geographical 

 notes of this group. The true H. fatigiata is described by 

 Shuttleworth (1. c.) and figured by Deshayes under a wrong 

 name, as well as placed in the text of his work among the 

 synonyms of Texasiana. PfeifFer in both of his works 

 considers it as a variety (distinctius carinata) of Texasiana, 

 and in Malac. Blatt, 1856, p. 11, declares Shuttleworth's 

 notes on it unsatisfactory. DeKay has placed it in the 

 genus Helicina. 



In the Boston Journal, Binney joins pustula to this 

 species, though doubtfully. By his notes, taken at the 

 Jardin des Plantes, it appears the species occurs there 

 under the name of operculata Val. 



Bland has corrected the errors of previous writers, and 

 thus points out the distinguishing characteristics of the 

 species. 



H. fatigiata Say is larger than Troostiana Lea, plicata Say, 

 and DorfeuiUiana Lea ; it is most nearly allied to the first, and 

 through it is connected with the second, but wholly distinct from 

 the last. The parietal tooth is more rectangular than that of Troos- 

 tiana, in which it is slightly emarginate near the tip, — but much 

 more so in plicata, while the parietal tooth in DorfeuiUiana is 

 rather quadrate. The teeth on the peristome in fatigiata and 

 Troostiana are much alike, as regards form, size, and position, — 

 the superior one being the largest, — both are larger and trans- 

 vei'se in Dorfeuilliana and in plicata, the inferior one being the 

 largest in the latter. Behind the pei'istome there are two small 

 pits, showing the situation of the teeth in fatigiata and Troostiana, 

 while there is scarcely more than a deep, well marked constriction 

 in DorJeuHliana. H. Troostiana has a slight groove on the inner 

 side of the last whorl, the absence of which in fatigiata is noticed 



