GASTEROPODA. 131 
obducta ; labro acuto: columella valde arcuata et excavata, postice callo 
tuberculoso copioso instructa. 
Melanopsis Zelandica, Goutp; Proceed. Boston Soc. Nat. Hist., ii. 
225. July 1847. Expedition Shells, 47. 
Anta with an oblong foot, rounded at the corners, about half the 
length of the shell, of an ochreous, lilac-tinted colour, beautifully and 
thickly dotted with slate-colour. Anterior angles very slightly deve- 
loped, head half the width of the foot, trapezoidal, beautifully dotted 
with scarlet; tentacles subulate, half as long as the foot, with six or 
seven dark annuli; eyes on short, large pedicles at the outer base of 
the tentacles: above, pale reddish-brown, with pale granular dots, ar- 
ranged in longitudinal lines, as in the Limneide. 
SHELL solid, ovate-conic, shining, olive-coloured, with three dusky 
bands. Spire short, conic, acute; whorls three, the upper ones flat- 
tened and confluent at the suture, the lower whorl large, posteriorly 
flattened, anteriorly ventricose, and nearly the whole length of the 
shell. Aperture elliptical, channeled posteriorly, bluish within and 
banded with chestnut-brown; lip acute; columella excavated and 
strongly arcuate, posteriorly bearing a tubercular mass of callus. 
Length nine-tenths of an inch ; diameter nine-twentieths of an inch. 
Inhabits New Zealand; common in fresh water. 
A well-marked species, distinguished principally by its short, conic 
spire of three whorls, its greenish banded surface, its arcuated colu- 
mella, and the bluish colour of its brown banded aperture. Compared 
with M. prerosa (M. levigata, Lk.), it differs as follows: it is less elon- 
gated, has three whorls instead of six or seven; its colour is olive- 
green and banded instead of plain brownish; the last whorl is six- 
sevenths instead of three-fourths the length of the shell; the aperture 
is inore elliptical, three-fourths instead of less than two-thirds the 
length of the shell; the columella is much more excavated and arcuated, 
so as to curve decidedly downwards when in the crawling position ; 
the interior is bluish and banded instead of plain pale chestnut. 
Figures 146, 146 a, side and base of the shell with the animal ; 146 3, 
shell viewed by the aperture. 
