TERRESTRIAL MOLLUSCA INHABITING SOCIETY ISLANDS. 
:n 
P. Maupiensis, Garrett. 
Pitys Maupiensis, Garrett, Proc. Cal. Acad. Sciences, 1812, p. 204; Proc. Acad. Nat. Sci. 
Phil., 1873, p. 233, PL III, flg. 64. 
Patula Maupitiensis, Schmeltz, Cat. Mus. Godeff., v, p. 93. 
Helix Maiipitiensis, Pfeiffer, Mon. Hel., vii, p. 481. 
Very common, and confined to the small island of Maupiti. 
It may be distinguished from any other Polynesian species by its fine, crowdt'd, 
elevated (not costidate) striae, convex spire, numerous very narrow rounded whorls, 
numerous internal laminae and deep vertical umbilicus. The parietal lamimc an* three, 
rarely two, and sometimes the one on the columellar region is obsolete. Besides the 
usital four palatal laminae, there exist, sometimes, finer and shorter intermediate ones. 
P. PAEViDENS, Pease. Plate II, figs. 14, 14 a, 14 6, 14 c. 
Helix parvidens, Pease, Proc. Zool. Soc., 1861, p. 243. Pfeiffer, Mon. Hel., v, p. 220. 
Pitys parvidens, Pease, Proc. Zool. Soc., 1871, p. 474. 
Patula incerla, “ Mousson,” Schmeltz, Cat. Mus. Godeff., v, p. 93. 
Helix incerta, Pfeiffer, Mon. Hel., vii, p. 481. 
Very abundant and confined to Tahiti, Moorea and Iluaheine. Examph's from 
the three different localities are precisely alike as regards the character of tlie fine, 
rib-like stria;, size of the umbilicus and shape of the spire. There are generally two, 
rarely three, parietal laminae, and usually four, sometimes fi\ e in the palate. Taliiti 
and Moorea specimens are a little larger and darker-colored than those from Ilualieine, 
which latter have a cinereous base. 
P. CONSOBEINA, GaiTctt. Plate II, figs. 17, 17 a, 17 6, 17 c. 
Shell umbilicated, thin, orbicular, depressed, radiately striated with very fim*, 
crowded, nearly straight, membraneous riblets; yellowish horn-color, t<'ssellated and 
striped with reddish brown ; spire planulate ; suture channeled ; wliorls six, very narrow, 
convexly rounded, subangtdate next to the suture, slowly and regularly increasing, tlie 
last one not deflected in front, much deeper than wide, obtusely rounded on the 
periphery; base convex; umbilicus perspective, showing all the whorls, nearly a third 
the greater diameter of the shell ; aperture vertical, narrow, irregidarly orbicular- 
lunate ; parietal region with four (very rarely three), and tlie palate with from seven 
to nine lamina' ; peristome thin, straight, simple with remote margins ; columella with 
or without a lamelliform plait. 
Major diam. 3, height 1| mill. 
Hob. — Huaheine Island. 
Rare and peculiar to one valley. The spire is more planulate and the body-whorl 
deeper than parvidens. It also has one more whorl, and the lamime are much more 
numerous than in the latter species. 
P. suBTiLis, Garrett. Plate II, figs. 15, 15 a, 15 6, 15 c. 
Shell umbilicated, orbicular, depressed, thin, yellowish corneous, tessellah'd and 
