40 ASSIMINIID. 
oval, angulated above; peristome fuscuous, double ; the internal one 
continuous ; the external narrowed at the penultimate whorl, in other 
respects, opened, slightly reflexed. 
Length, -27 ; diam., ‘13; aperture, length, ‘08. (Pfr.) 
Drury. ‘Taupiri (Hochstetter.) 
Genus, OMPHALOTROPIS—Pfeiffer. 
Operculum thin, horny, few whorled. Shell perforated, or narrowly 
umbilicated, turreted, or globosely-turbinated, keeled around the 
perforation ; aperture oval; peristome disconnected, straight or ex- 
panded. 
O. vestita, Pfeiffer; P.Z.S., 1855, p. 106; A, Pn. V., Suppl. 1, 
p. 166 ; Omphalotropis vestita, Pfr, M. Pn. V., Suppl. 2, p. 179, Wo. 
30. Shell perforated, oblongly-conical, thin, striated and spirally closely 
ridged, covered with a somewhat fuscuous epidermis ; spire pyramidical, 
rather acute ; whorls 6, flat, the last armed below the middle with an 
acute keel, and about the perforation with a second ; aperture hardly 
oblique, sub-angularly oval; peristome simple, straight, margins con- 
verging. Operculum fuscous. 
Length ‘2; diam., ‘12 ; aperture, length, ‘08. (Pfr.) 
New Zealand. 
FAMILY—ASSIMINIID/:. 
Foot moderate, flat. Lingual teeth 7-5 cusped, the first and second 
uncini dentated, the third rounded. Head rostrate, produced and 
emarginate anteriorly ; eyes on the middle of the tentacles, near the 
tip. Shell covered with a horny epidermis. Operculum horny, sub- 
spiral. 
Genus, ASSIMINEA—Leach 
Tentacles short, obtuse, with the eyes near the ends. Operculum 
horny of few rapidly increasing whorls. Shell ovato-conical, with the 
spire more or less produced ; whorls flattened ; axis not perforate, or 
slightly rimate ; aperture ovate, entire, columellar lip thickened, outer 
lip acute. 
Europe. India. Tasmania. Polynesia. 
In this genus the body is small, and the head produced into a 
ringed muzzle. The foot is large, broad in front, short and rather 
obtuse behind. Amphibious, generally in brackish water. 
A. purchasi, Pfeifer; P.Z.S., 1861, p. 150; M. Pn. V., Suppl. 
2, p. 172, No. 13 (Hydrocena.) Shell sub-perforated, turriculated, 
somewhat smooth, translucid, horny-fuscous ; spire conical, rather 
obtuse ; whorls 5, convex, the last slightly exceeding one-third of the 
entire length of shell; aperture a little oblique, sub-circular ; peristome 
simple, straight, very shortly interrupted at the contiguous whorl, left 
margin slightly reflexed.  ~ 
Length, *o8);"diam., “o4. ((Pit:) 
