HELIX-AMPELITA. 47 



margined with rufous at the suture, tumid, impressed in the middle, 

 encircled at the periphery by a narrow rufous zone, angulated and 

 then rounded, slightly descending and broadly dilated at the aper- 

 ture ; convex below, angulated around the umbilicus and encircled by 

 a broad rufous zone ; aperture oblique, lunate, within bright white, 

 ovate-subquadrate ; peristome obtuse, expanded, reflexed, slightly 

 thickened, the margins converging, joined by a shining white callous ; 

 outer margin at first nearly straight, then curved, sinuous, broadly 

 expanded, reflexed, basal margin shortly arcuate ; columellar ob- 

 liquely descending, straightened, thickened, narrowly reflexed. Alt. 

 14, greater diam. 29, lesser 27 mill. The size and form resemble 

 those of H. thelica ; it is thicker, more solid, rather shining, orna- 

 mented with 3 clear chestnut bands ; the first sutural, the second 

 narrow at the periphery, bounded by a depression on the last whorl ; 

 finally the third, occupying the greater part of the base. The spire 

 is very small, conic, mammillated ; the umbilicus moderate, much 

 covered relative to its size, yellow inside, and bounded by an appre- 

 ciable angulation. (Mabille, 1. c., p. 141.) 



Madagascar. 



H. thelica Mabille. Shell narrowly, subperviously umbilicated, 

 conic-depressed, solid, little shining, rufous-yellowish, under a lens 

 very minutely reticulate-decussate ; spire subconvex, little prominent ; 

 apex obtuse, whitish ; whorls 5, subregularly, rapidly increasing, 

 first whorl plano-convex, whorls separated by impressed suture, the 

 last large, somewhat turgid above at the suture, impressed in the 

 middle, obtusely angulated at the periphery, dilated and shortly de- 

 scending at the aperture, convex below, obscurely angled around 

 the umbilicus ; aperture oblique, lunate, irregularly ovate ; peris- 

 tome white, patulous, a little reflexed, a little thickened ; margins 

 subapproximating, the outer dilated, well curved, columellar a little 

 incurved. Alt. 13, greater diam. 28, lesser 22 mill. A small Helix, 

 in general form like H. lamari, but differing in the smaller size, 

 more solid shell, less rapid increase in the earlier whorls, the last 

 more descending, and with a well-marked circular depression ; the 

 umbilicus is more open than in the lamari. Finally, the base of H. 

 thelica has the form of a truncated cone. (Mabille, 1. c., p. 142.) 



Madagascar. 



H. monacha Mabille. Shell narrowly, pervicrusly umbilicated, de- 

 pressed-orbicular, shining, little thick, solid, closely and pretty ir- 

 regularly striate, white under a deciduous epidermis, ornamented with 



