TERRESTRIAL MOLLUSC A INHABITING SOCIETY ISLANDS. 
19 
M. VERTiciLLATA, Pease. Plate II, figs. 31, 31 a, 31 h. 
Nanina verticillata, Pease, Amer. Jour. Conch., 1867, p. 228. 
Helix verticillata, Pfeiffer, Mon. Hel., vii, p. 66. 
Helicopsis verticillata, Pease, Proc. Zool. Soc., 1871, p. 475. 
Nanina cicercula, var. “ Mousson,” Schmeltz, Cat. Mus. Godeff., v, p. 91. 
Helix brunnea, Carpenter (Anton?), Proc. Zool. Soc., 1864, p. 675. 
I found this species very abundant beneath moist rotten wood and amongst 
decaying leaves, on the north part of Moorea, and more rarely at Iluahcine. 
It is about the size and shape of M. cicercAila, Gould, a Sandwich Island spc'cies. 
but differs in liaving a rounded periphery and more convex whorls. I'lie Iluahcine 
shells are a little larger and darker colored than Moorea specimens. The former 
have the inner edge of the columella simply thickened with callus, and in the lattei 
the callus is frequently developed into a slight tubercle or somewhat tu isted plait. 
My largest examples are 7 mill, in diameter. 
M. SIMILLTMA, Pease. Plate II, figs. 32, 32 a, 326. 
Helix simillima, Pease, Proc. Zool. Soc., 1864, p. 669. Pfeiffer, Mon. Ilel., v, p. 50. 
Helicopsis simillima, Pease, Proc. Zool. Soc., 1871, p. 475. 
Nanina simillima, Schmeltz, Cat. Mus. Godeff., v, p. 207. 
A somewhat rare species, peculiar to Eaiatea, where it occurs high up in the 
mountain ravines, and is found beneath moist decaying leaves and under rotten wood. 
]Mr. Pease, who received his type specimens from me, correctly labeled as regards 
locality, gave the vague habitat “ Central Pacific,” and subsequently “Tahiti,” where 
it does not occur. His brief diagnosis is not very satisfiictory. I add the following 
description : — 
Shell orbicular, depressed, thin, smooth, shining, pellucid, fiiintly striated, yellowish 
corneous; spire slightly elevated, convex, apex obtuse; suture faintly inijiressed, 
narrowly margined; whorls 3i-4, flatly convex, regularly and rather rapidly increasing, 
the last one not descending in front, depressed, periphery rounded ; base flatly convex 
and deeply indented at the axis; aperture ovately lunate, nearly vertical; peristome 
thin, straight, regularly curved, with remote margins and simple columella. 
Major diam. 10, height mill. 
Its large size, depressed form, and rather rapidly increasing whorls, will readily 
distinguish it from any other South Polynesian species. 
M. NOBMALis, Pease. Plate II, tigs. 33, 33 a, 336. 
Helix normalis. Pease, Proc. Zool. Soc., 1864, p. 669. Pfeiffer, IMon. Ilel., v, p. 59. 
Helicopsis normalis, Pease, Proc. Zool. Soc., 1871, p. 475. 
Nanina normalis, Schmeltz, Cat. Mus. Godeff., v, p. 91. 
Very abundant beneath rotten tvood at Tahiti, Moorea and Iluahcine. I add the 
following characters omitted by Mr. Pease in his short description . 
It varies in the height of the spire, the apex is obtuse, and the suture is margined 
