186 HELIX-RHAGADA. 



specimens these are diaphanous and colorless) one of them a little 

 above the periphery, being broader, and of a deeper color than the 

 rest ; spire moderately raised ; whorls 4J-5, slowly increasing, the 

 last conspicuously descending near the lip ; aperture very oblique, 

 rhomboidal-lunate ; peristome white, thin, shortly expanded at the 

 umbilical region, spread over the whorl in the form of a thin callos- 

 ity, concealing the perforation and united to the lip above. (Smith.} 



Alt. 12, greater diam. 19, lesser 16 mill. 



Depuch's Is., West Coast of Australia- 



H. Eichardsonii E. A. SMITH, Voy. H. M. S. Erebus and Terror,. 

 ZooL, Moll., p. 2, t. 4, f. 14. 



This species is allied to H. Keinga ; it differs in being of larger 

 and thinner growth, in the number of the whorls, which are not so 

 convex, being nearly one less, and in having the under side of the 

 last whorl, which is proportionately larger, more flattened, especi- 

 ally at the umbilical region which is overspread by a broadish thin 

 callosity, united above to the outer lip. The greater deflection of 

 the last whorl near the mouth is another notable difference, and 

 the peritreme is thinner and more expanded. (Smith.) 



H. LEPTOGRAMMA Pfeiffer. Vol. IV, pi. 36, fig. 33. 



Shell umbilicated, globose, thin, striate, sculptured with close, con- 

 centric, impressed lines, fleshy-whitish, ornamented above with three 

 or four narrow reddish bands. Whorls 4 J, a little convex, the last 

 one inflated, shortly descending in front. Aperture scarcely oblique, 

 rotund-lunar, concolored within ; peristome white, simple, slightly 

 expanded, margins joined by a diffuse very thin callus, the columellar 

 margin much dilated, white, shining, reflexed, half covering the nar- 

 row umbilicus. (Pfr.) 



Alt. 13, greater diam. 17, lesser 14 mill. 



Cygnet Bay, North Australia* 



H. leptogramma PFR. P. Z. S. 1845, p. 127 ; Monogr. i, p. 322. 

 KEEVE, Conch. Icon., f. 437. Cox, Monogr. Austr. L. Sh., p. 41, t. 

 11, f. 4. E. A. SMITH, Zool. Erebus & Terror, Moll., p. 2, t. 4, f. 18. 



H. DRINGI Pfeiffer. Vol. IV, pi. 36, fig. 40. 



Shell covered-umbilicate, depressed, thin, fragile, closely plicate- 

 striate above, whitish, opaque, encircled by pellucid lines; spire 

 nearly flat ; whorls 4?, scarcely at all convex, the last one somewhat 

 compressed laterally, base smooth, inflated. Aperture lunar, con- 



