GASTEROPODA. 107 
cially the upper ones; moderately convex, somewhat contracted poste- 
riorly, so that each whorl overhangs a little the succeeding one in a 
sort of imbricated manner ; acuminated at tip. Aperture rather large, 
nearly round, a little angular behind, orange within. Lip simple, 
campanulate, touching the preceding whorl about one-quarter of its 
circuit. Umbilicus free, fissure-like, margined by a faint angle. 
Breadth one-tenth of an inch; length one-fourth of an inch. 
Found at Tahiti and Eimeo, at an elevation of 3500 feet. Cou- 
thouy. 
Distinguished from other similar species by its acuminated spire, 
angular, imbricated whorls, and expanded aperture. Its general form 
and appearance is like Pupa fallax, Say. 
Figure 120, an elongated specimen, and figure 120 a, a short speci- 
men, enlarged ; 1204, natural size. 
CycLosToMa VaLLAtTuM (Gould). 
Testa parva, solida, elongato-conica, lucida, fusco-cornea: spira anfrac- 
tibus sex convexis, sub-angulatis, ultimo costa valida umbilicum ambi- 
ente munito: suturd profunda: apertura oblique ovata; peristomate 
continuo, simplict, campanulato. 
Cyclostoma vallatum, Goutp; Proceed. Boston Soc. Nat. Staats 
206. March 1847. Expedition Shells, 39. 
SHELL small, ovate, elongated, rather thin, translucid, polished, 
bronzy horn-colour, umbilicate. Whorls six, convex, the last whorl 
with an obtuse angle at the periphery, which also appears near the 
suture of the other whorls as it winds up the spire. ‘There is also, 
revolving about the umbilicus, a rib-like ridge; suture channeled. 
Aperture obliquely ovate, with the lip continuous and slightly ex- 
panded, but not reflexed. 
Length of axis one-sixth of an inch; diameter one-twelfth of an 
inch. 
Inhabits the Tonga Islands. Drayton. 
