26 HELIX-AMPELITA. 



t 



Var. SAKALAVA Angas. PI. 5, figs. 68, 69, 70, 71 ; pi. 63, fig. 45. 



Entire surface chestnut or chocolate brown, freckled and zigzag- 

 streaked with opaque yellowish ; a light yellow zone on the angle 

 surrounding the umbilicus, within which is a dark band ; inside of 

 the umbilicus light yellow. 



Alt. 18, greater diam. 37, lesser 28 mill. 



A color-variety having freckled brown zones on a pale green, 

 ground is figured on pi. 63. fig. 45. 



. s 



H. WATERSI Angas. PL 5, figs. 72, 73. 



Shell with a small, compressed umbilicus, discoidal, rather solid,, 

 obliquely closely striated with irregular somewhat undulating erect 

 stride, which are crossed by numerous concentric lines, exhibiting 

 here and there a minutely reticulated appearance at the points of 

 crossing; light purplish-brown, becoming darker behind the lip, 

 partially covered with a pale straw-colored epidermis ; spire depressed,, 

 whorls 4, rapidly increasing, somewhat convex, the last very wide, 

 swollen, bluntly keeled, with a slight depression above the keel ;. 

 aperture nearly horizontal, transversely Innately ovate, margined 

 within with a broad band of purplish-black, interior pale lilac ; peri- 

 stome thickened, expanded and reflected, edged with white ; margins 

 approximating and joined by a callus. {Angaa.} 



Alt. 18, greater diam. 41, lesser 32 mill. 



Ekongo, $. E. Coast of Madagascar. 



H. watersi ANGAS, Proc. Zool. Soc. Lond. 1877, p. 527, t. 54, f. 3. 



Distinguished from H. sepulchralis and its allies by its elaborate 

 sculpture and by the expanded form of the aperture. 



Group of H. omphalodes Pfr. 



The form is depressed but not lenticular; bluntly carinated at 

 times, but never acutely or conspicuously so, as it is in the closely 

 allied group following. The peristome is narrowly reflexed all 

 around, but a little more broadly above. The species are mostly 

 banded ; the umbilicus is moderately wide, circumscribed by a 

 blunt angle. 



(1.) Basal lip of the aperture nearly straight, the columellar lip 

 short, narrowly expanded, forming a blunt angle where it joins the 

 basal margin. H. omphalodes, loucoubeensis, calypso, basizona, con- 

 sanguinea, guillani. 



