TERRESTRIAL MOLLUSCA INHABITING SOCIETY ISLANDS. 
103 
Helicina Rolvii, Carpenter (not of Pfeiffer), Proc. Zool. Soe., 1864, p. 616. Schmeltz, Cat. 
Mus. Godeff., v, p. 207. 
Helicina albolabris, Schmeltz (not of Homb. and Jacq.), Cat. Mus. Godeff., v, p. 98. 
M. Lesson’s description, which Pfeiffer has copied, being very brief, I redescribe it 
as follows : — 
Shell solid, conoid, opaque, smooth, somewhat shining, with crowded, faint strim ; 
color variable, generally brownish red, gradually fading on the body-whorl into 
whitish, pale yellowish or corneous ; aperture and basal callus white or bluish white ; 
spire convexly conoid ; whorls 4|— 5, flatly convex ; aperture very oblique, small, semi- 
oval ; peristome slightly expanded, thickened, somewhat labiate, emarginate above the 
periphery ; columella short, arcuate ; callus semicircular, thickened towards the 
extremities of the peristome. Operculum yellowish horn-color. 
Major diam. 9, less. diam. 7, height 6 mill. 
Hab. — Borabora Island. 
Lesson’s shells were procured in the same location, where it is peculiar. They 
occur abundantly on the trunks and foliage of trees and bushes in the mountain 
forests. 
It is subject to the following variations : — 
a. Uniform white. 
b. Uniform yellow, with white callus. 
c. Pale lemon-yellow, with a spiral brownish red band. 
H. iNCONSPicuA, Pfeiffer. 
Helicina inconspicua, Pfeiffer, Zeits. Malak., 1848, p. 86 ; Mon. Pnenm., i, p. 357. Chem- 
nitz, ed. 2d, p. 26, PI. IX, figs. 18-21. Gray, Cat. Phan., p. 258. (Idesa) H. and A. 
Adams, Gen. Moll., ii, p. 304. Pease, Proc. Zool. Soc., 1871, p. 476. Schmeltz, Cat. Mus. 
Godeff., v, p. 99. 
Helicina exigua, Hombron and Jacquinot, Voy. Pol. Sud, v, p. 46, PI. XI, figs. 32-35. 
Pfeiffer, Mon. Pneum., ii, p. 187. Pease, Proc. Zool. Soc., 1871, p. 476. 
Helicina minuta, Carpenter (not of SowerbyJ, Proc. Zool. Soc., 1864, p. 676. 
Helicina decolorata, “ Mousson,” Schmeltz, Cat. Mus. Godeff., v, p. 99. 
This, the smallest species inhabiting the group, is not uncommon, and is diffused 
throughout all the islands, where they occur on the ground in forests, and range from 
near the seashore to 1000 feet above sea-level. I also obtained examples at the 
Gambier Islands = Mangareva, which differed none from Society Islands specimens. It 
is n. exigim, H. and J. . „ v 
The peristome, though usually straight and simple, is occasionally slighth 
expanded, and they vary slightly in the depression of the body-whorl. The coloration 
is uniform reddish brown, brownish horn-color, corneous, and more larely luteous 
horn-color. The operculum is corneous, with a wide Hat external ridge. Specimens 
collectetl at Maupiti are frequently marked by fugations, delicate spiral lines similar 
to II. flavescens. 
