GASTEROPODA. 83 
sometimes pure dead white, in other specimens yellowish flecked with 
white, in others more or less fawn-coloured, striped longitudinally 
with irregular zigzag lines, which are sometimes anastomosing ; strie 
of growth delicate, with crowded, very fine revolving lines. Spire 
acute, of nearly five rounded whorls, the last of which composes 
three-fourths the length of the shell, and is much reflected. Suture 
margined. Aperture oval, modified by the last whorl. Peristome 
broad, thin, white, flattened, and inwardly strengthened so as to 
bound the aperture with a sharp right angle, and to contract the 
orifice. At the columellar margin is a pretty large fold, which 
answers to an umbilical fissure. 
Length four-fifths of an inch ; breadth half an inch. 
Inhabits Upolu and Tutuila, Samoa Islands, on Dracena borealis. 
Couthouy ; Drayton ; Case. 
A rather large and very fine species, more ventricose than others, 
and distinguished by its perfectly flattened peristome as well as by its 
variegated colouring and revolving stri#. It somewhat resembles 
Bulimus versicolor. 
Figure 89, a dark shell, with the animal ; 89 a, the pale variety. 
PaRTULA PUSILLA (Gould). 
Testa parva, elongata, conica, polita, albido-cornea, perforata: spira 
acuta, anfractibus sex convexis, superné tabulatis : apertura sub- 
quadrata, posticé lamella intro-volvente instructa ; peristomate reflexo, 
dextrorsum sinuato. 
Partula pusilla, Govtpv; Proceed. Boston Soc. Nat. Hist., ii. 197. 
Expedition Shells, 33. 
SHELL minute, elongated, conical, rather thick, smooth and shining, 
of a light horn-colour, moderately umbilicated. Spire acute, com- 
posed of six moderately convex whorls, which have a small shoulder 
posteriorly. The aperture is direct, somewhat quadrangular, having 
