North American Helices. 29 



various observations on the fulcrum and its modifications, but 

 some further explanation on the subject is necessary. 



The following species have the same form of that accessory 

 process as prevails in spinosa, the type of Stenotrema, viz. : 



II. monodon M. & It. H. hirsuta Say. 

 barbigera Redf. labrosa Bid. 



Edvardsi Bid. maxillata Gould. 



Edgariana Lea. leporina Gould, 



stenotrema Fer. pustuloides Bid. 



A simple, small, transverse tubercle, which I have called a 

 modification of the fulcrum, is found in — 



H. pnstula Fer. H. Troostiana Lea. 

 tholus W. G. By. fastigans L. W Say. 



" var. Mooreana W. G. By. hippocrepis Pfr. 



Dorfeuilliana Lea. loricata Gould. 



In my " Notes" above referred to I placed II. Hazardi in 

 section " D. Lip reflected, with fulcrum ;" but in my " Re- 

 marks" {Annals VI. 393) I more correctly described it as 

 follows : — 



" In H. Hazardi the inferior tooth of the labrum, at its inner end, is 

 continued back within the aperture, forming a white, erect lamella on 

 the floor of the whorl, parallel with, and leaving a narrow sinus between 

 it and the inner wall, to which it is joined at its extremity, about 2£ mill, 

 from the edge of the peristome." 



In II vultuosa and its near ally II. i?itrqferens, the lamella 

 on the lower lip is continued within the aperture, where it ter- 

 minates in a somewhat diagonal, elevated callus. 



The lamella in Hazardi, and callus in the two above named 

 species, placed much nearer to their apertures than the fulcrum 

 or tubercle in those enumerated in the two preceding lists, can 

 scarcely, perhaps, be considered as modifications of the fulcrum. 



It will be noticed that Albers places in Stenotrema H.pustula, 

 also H. Lecontii Lea from California (the latter as loricata 

 Gould, which name has priority, in Triodopsis), both having the 

 tubercle as in Troostiana and other species put by Albers in 



