90 HELIX-DENTELLARIA. 



tion and scarcely obvious scrobiculation behind the peristome will 

 separate this species from H. josephinse and lychnuchus. It is more 

 nearly related to H. formosa than to any of the other species. 



H. FORMOSA Ferussac. PL 29, figs. 34-36. 



Imperforate, depressed-globose, solid, opaque, slightly shining, 

 straw-colored, with two broad dark chestnut bands, covered with a 

 coarse network of silvery maculations and streaks ; surface rather 

 coarsely granulose, the granulation generally subobsolete except on 

 the base ; spire low, rounded, apex flat ; sutures linear ; whorls 4, 

 nearly flat, slowly widening, the last depressed-subglobose, rounded 

 at, the periphery, very deeply descending anteriorly; aperture 

 oblong-oval, nearly horizontal ; peristome broadly expanded, contin- 

 uous, white or orange-brown ; basal margin horizontal, widened by 

 a plate-like callus within, which is abruptly truncated at the union 

 of basal and outer lips, the truncation marked behind the peristome 

 by a very slight depression. Terminations of the peristome united 

 across the parietal wall by an elevated callus. 



Alt. 14, diam. 24 mill. ; alt. 10, diam. 18 mill. 



Antigua; Barbuda* 



H. formosa FEE. Prodr. 67. PFR. Conchyl. Cab. p. Ill, 1. 15, f. 14 

 -16 ; fiymb. ii, p. 28 ; Monogr. i, p. 308. H. lenoeinia FER. Hist. t. 

 47, f. 1. Dentellaria formosa BECK, Index, p. 34. W. G. BINNEY, 

 Ann. N. Y. Acad. Sci. iii, 1884, p. Ill, t. 16, f. R, and t. 9, f. H. (Jaw 

 and dentition.) 



The horizontal, oval aperture, continuous peristome and peculiar 

 painting of this form are very characteristic. The shells from 

 Barbuda are small, body-whorl carinated. The species is allied to- 

 ll, perplexa. 



H. PACHYGASTRA Gray. PI. 28, figs. 18-20. 



Imperforate or subperforate, globose-depressed, solid, opaque,, 

 shining, chestnut colored, with delicate lines of increment; not 

 granulated ; spire very low, convex ; apical whorl flat ; sutures 

 linear, a little impressed on the last half of the outer whorl ; whorl& 

 4, a trifle convex, penultimate about as wide as the last ; body-whorl 

 depressed, rounded, but with a carina around the periphery, scarcely 

 at all deflexed anteriorly ; aperture oblique, transverse, subrhom- 

 boidal ; peristome flesh-colored or brown, slightly expanded, thick- 

 ened, convex, its right extremity obtusely angled at the position of 

 the periphery ; lower margin bearing on its outer part a large, com- 



