North American Helicidce. 49 



Helix albolaM'is l§ay. 



SYNONYMY. 



Helix albolahris Say Nicli. Encyc. (Amer. Ed.) IV. p. 181, pi. 1, fig. 1. 



1816. 



» " Amer. Conch. No. 2, pi. 13, 1831. 



« Binney Best. Jl. I. p. 475, pi. 13, - 183Y. 



major " " " 473, " 12, 



albolahris Chemn. ed. 2, Helix, p. 81, pi. 15, fig. Y, 8. 



" Zfcs/i. in Fer.Histp. 13'7,pl.43,fig.l-5,pl. 40 A, fig. 7. 



" Pfr. Mon. I. No. 757, 1848. 



major Binney Terr. Moll. H. p. 96, pi. 1, 1851. 



albolahris " " " " 99, pi. 2, " 



" i?eei'(? Conch. Icon. fig. 624, 656, 1852. 



" W. G. Binney Reprint of Say, p. 5, 33, 1857. 



Say thus describes this species in Nicholson's Encyclopsedia, — 



"H. ALBOLABRIS. 



"Shell thin, fragile, convex, imperforated; with six volutions, whorls 

 obtusely wrinkled across, and spirally striated with very fine impressed 

 lines, a little waved by passing over the wrinkles, both becoming extinct 

 towards the apex, which is perfectly smooth; aperture lunated, not 

 angulated at the base of the column, but obtusely curved, lip contracting 

 the mouth abruptly, Avidely reflected, flat and white. 



"Length of the column three-fifths of an inch ; breadth one inch." 



The form of the shell referred to by Say has been confounded 

 by European authoi's with H. exoleta Binney [11. zaleta Say), 

 from which, however, it is entirely distinct. Dr. Leidy, from 

 whom I sought information on the subject, wrote to me in 1857 

 as follows: "There is no doubt, I think, that 11. alholahris and 

 H. exoleta are distinct species, as their internal anatomy is 

 quite different." This effectually disposes of the hypothesis of 

 Deshayes, who, writing of the latter species (Fer. Hist.), re- 



