48 HELIX-AMPELITA. 



a broad brown zone ; spire a little convex, scarcely prominent, apex 

 minute, obtuse, rugose; whorls 5-5?, a little convex, visibly widen- 

 ing, separated by a narrow, well-impressed suture, the last sloping 

 above, obscurely angular at the periphery, dilated and briefly de- 

 flexed at the aperture, somewhat tumid beneath, chestnut tinted at 

 the umbilicus and rounded, a little constricted behind the peristome. 

 Aperture very oblique, lunate ; peristome thickened, livid, narrowly 

 reflexed, obtuse ; margins approximating, joined by a rather thick 

 callus, outer margin subsinuous, basal broadly subappressed, colu- 

 mellar margin very short, concave, dilated. Alt. 19, greater diam. 

 44-45, lesser 36-37 mill. In the H. monacha the spire is relatively 

 little developed, feebly convex-conic ; the whorls are little salient ; 

 the last forms nearly two-thirds the entire shell, is feebly convex 

 above, and a little sloping as far as the periphery ; it is rounded and 

 then obliquely swollen below. The umbilicus is narrow, little 

 spreading, penetrating, tinted with reddish-brown. The peristome 

 is livid flesh-colored, a little reflexed, narrowly thickened, obtuse, 

 nearly continuous in consequence of the presence of a callous unit- 

 ing the insertions, feebly interrupted in the middle by the parietal 



wall. (Habille, 1. c., p. 1 43.) 



Madagascar. 



If. cyanostoma Mabille. Shell broadly umbilicated, depressed- 

 orbicular, solid, little thick, subshining, more or less striate and 

 often here and there malleate, white under a fulvous or blackish 

 deciduous epidermis, rufous zoned at the suture ; spire convex, little 

 prominent, apex valid, obtuse, costulate, whitish ; whorls 5-5 ?, sub- 

 planulate, rapidly and subregularly increasing, separated by im- 

 pressed sutures, the last large, dilated and a little descending in front, 

 obscurely angulated at the periphery, planulate beneath, tinted with 

 black at the umbilicus, scarcely rounded; aperture oblique, obscurely 

 tetragonal-ovate ; peristome a little thickened, broadly expanded, 

 reflexed ; margins converging, the outer arcuate, basal straightened 

 somewhat, columella oblique, scarcely incurved. Alt. 16-18, diam. 

 maj. 41-46, min. 33-41 mill. This large and beautiful form has a 

 thin but quite solid shell, of a brown color verging a little on red ; 

 it is distinctly striate ; the stria? a little spaced and oblique, are 

 accompanied by some malleations. The aperture presents within a 

 beautiful blue shade with brilliant reflections. The umbilicus is 

 wide, quite open, regularly circular, little angular at its edge and 

 widely penetrating. (Mabille, 1. c., p. 144.) 



Madagascar. 



