North American HelicidcB. 57 



St. Auffustiiie, and several of the rare H. avara from the 

 vicinity of the river St. John, East Florida. After careful 

 examination of the whole subject, I am of opinion that IL 

 auriculata Say, and avara Say, are entirely distinct, — that the 

 forms referred to by Dr. Binney as avara, and byhim, PfeifFer, 

 and Deshayes, as varieties of auriculata, are likewise distinct, 

 and that the comparatively small shell commonly labelled 

 S^. auriculata in our cabinets, but generally without authentic 

 habitat, is a variety of 11. uvulifera Shuttl. 



Pfeiffer in Mon. I. refers to Ferussac's figure 3 (pi, 50), as 

 var. minor of II. aur'iculata, but with doubt in Mon. IIL to 

 the same, in the synonymy of H. uvulifera Shuttl. 



Reeve's fig. 700 (pi. 119), referred to by Pfeiffer as auriculata, 

 appears to be of the same form. 



Deshayes gives an elaborate description in French of this 

 species ; alluding to the variety, he says : " La variete est plus 

 petite, plus mince, plus transparente : mais ces caracteres 

 dependent probablement de lage, II en est sans doute de 

 meme relativement aux differences dans les formes et les pro- 

 portions de I'ouverture." He derived and adopted, I presume, 

 that opinion from the Boston Journal. 



To aid in identifying this and the allied species, I give the 

 anneS;ed figure I. of the aperture of H. auricu- Fio. i. 



lata Say, double the natural size, taken from a 

 living specimen collected by Mr. O. M. Dorman 

 at St. Augustine. 



H. auriculata may be distinguished by its 

 larger size, the greater development of the seve- 



1 1 i> •, ' , 1 • n fi". auriculata Say. 



ral parts oi its curious aperture, and especially 

 by the sudden outward deflexure of the central part of the 

 labrum, which has a deep scrobiculation behind it, correspond- 

 ing with the upper tooth within the aperture. The portion of 

 the labium extending from the inferior angle of the parietal 

 intruded tooth is erect, and more elevated than in any other of 

 the species. 



