HELIX. 119 



surface, rising a little towards the apex; the whorls, which are 

 distinctly marked, are beautifully striated with delicate prominent 

 curved lines, which are crowded towards the apex, and separated 

 by a distinct interval on the outer whorl ; they terminate on the 

 edge of the carina, which is a little plaited by them, the base below 

 being smooth. The aperture is narrow, and marked by an angle at 

 the carina. The lip below the carina has a distinct, though narrow 

 reflection. The umbilicus is moderate, conical, and rather deep, 

 exhibiting about three volutions. In Lamark's arrangement it 

 would be a Carocolla. 



HELIX INDENT ATA SAY vol. ii. p. 242, pi. xxix. fig. 2. 



Helix indentala SAY, (Binney's ed.) p. 24. 

 CHEMNITZ, i. 221, (1846). 

 REEVE, Con. Icon. No. 730, (1852). 

 PFEIFFER, 1. c. iii. 65. 



Found also in Florida, Canada, and Texas, (Moore). 

 For its supposed presence in St. Domingo, see Mai. Bl. 

 5, 147. 



HELIX CHERSINA SAY vol. ii. p. 243, pi. xvii. fig. 4. 



Helix chersina SAY, (Binney's ed.) pp. 18, 31. 



Helix fulva teste MIGHELS, (Bost. Journ. iv. 333,) CHEMNITZ, PFEIFFER, 



REEVE, FORBES and HANLEY. 



I have separated the synonymy of H. egena Say, from 

 that of chersina, since many authors consider them dis- 

 tinct. The typical chersina is well represented in the 

 plate. The original specimen of egena is readily distin- 

 guished from it by having a short, pyramidal, acute spire, 

 and a very rounded base, the separation of the two being 

 very well defined. There exist, however, innumerable 

 gradations between these extreme forms. It must be 

 borne in mind, that the shell figured and described by 

 Gould on p. 245, is not egena Say, but Gundlachi Pfr. 



I give Say's description below. 



II. EGENA. Shell convex, polished ; whorls five, not distinctly 

 wrinkled, rounded ; aperture rather narrow, transverse ; labrum 



