Sea Shells. 
of New Zealand 
Plate VI 
No.7 
Plate VI 
No.5 
Plate VI 
No. 4 
about an inch or more in height, and the same in transverse 
diameter. 
Throughout New Zealand; Mount Maunganui. 
MONODONTA ATROVIRENS (monos, one; odous, 
odontos, a tooth; atrovirens, blackish green ).—A greenish- 
black solidly-built spiral univalve, very similar to the M. 
Aethiops, except for the absence of the white tessallations 
and having small yellowish dots scattered irregularly over 
the whorls. As these latter are by no means conspicuous, 
they must not be regarded as a trustworthy feature of the 
species. The outer lip is sharp, edged with black, followed 
by a broad silvery band. The inner lip is always bordered 
with a green streak. Full-grown specimens may be as 
much as an inch and an eighth in height, with a diameter 
of a sixteenth less. 
On rocks between high and low-water marks. 
Tasman Bay; west coast of North Island; Hauraki 
Gulf; Mount Maunganui; Lyttelton; Dunedin. 
MONODONTA CORACINA (monos, one; odous, a 
tooth; korax, a crow).—A small black, lustreless univalve, 
with spiral grooves, about ten, on the body whorl, and fine 
deeply-marked growth lines crossing them, which form of 
sculpture gives the shell its dead black appearance, and 
incidentally its specific name as being black as a crow; 
the outer lip is sharp, with a well-marked black band lining 
it, followed by a broader white nacreous band descending 
to the base and forming the margin of the columellar lip. 
It then ascends and widens somewhat at the top of the 
aperture, forming a complete circuit of pearl, by which you 
may distinguish this species from several closely-allied 
species. The white opaque columella is prolonged into a 
tail-like process to the inner side of the pearly band at 
the base of the outer lip. The interior is pearly, alternately 
ribbed and grooved. At the base are a few, three or four, 
spiral rows of whitish dots, where the spiral grooves and 
growth lines have become worn. Found on rocks and 
boulders above low-water mark, About half an inch in 
height and a trifle less in width. 
St. Heliers’ Bay; Mount Maunganui; Kawhia; Welling- 
ton and Lyttelton Harbours; Sumner; Chatham and Auck- 
land Islands. 
MONODONTA CORROSA (monos, one; odous, odon- 
fos, a tooth; corrosa, corroded, or eaten away).—This 
species is much like the other members of the genus mono- 
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