donta, being small, of a dark purplish colour, and pearly 
internally. “Colour dark purple, overlaid with a more or 
less eroded, yellowish-white layer, leaving sometimes zig- 
zag bands purple on the last whorl.” (Suter). Adams 
describes it as “of a dirty blue.” The characteristic feature 
is a narrow band of yellow on the inner margin of the outer 
lip, followed by a narrow strip of black. This monodonta 
is very similar to the M. subrostrata, but may be dis- 
tinguished from that species by the colour band on the 
outer lip. Found on mud flats of the South Island. 
Portobello; Dunedin; Christchurch. 
MONODONTA EXCAVATA (monos, one; odous, a 
tooth; excavata, excavated or hollowed out).—A small 
conical spiral univalve, with an excavated or concave base, 
sculptured with indistinct spiral grooves and distinct growth 
lines. It is coloured a pale yellowish green, or greenish 
grey, crossed with oblique wavy dark-green bands or bars. 
The lower and widest part of the body whorl is angled, so 
that the whole shell lies flat upon its base. The mouth is 
large and oblique, pearly inside, with the light and dark 
bars of the body whorl showing distinctly through the thin 
shell by transmitted light. The outer lip shows the usual 
thin sharp edge of the monodontas, and has a more or less 
indistinct narrow black edging inside, with an opaque white 
band next to it. The inner lip is white and, with the um- 
bilical tract, takes up almost the whole of the base not 
occupied by the aperture. It is a small shell, about a quarter 
of an inch in diameter, slightly less in height, and is met 
with on the lowest parts of rocks, close to the sand, between 
tide marks. 
Found on the east coast at Mount Maunganui, on the 
west coast of both Islands, and at the Chathams. 
MONODONTA LUGUBRIS (monos, one; odous, odon- 
tos, a tooth; lugubris, sad, mournful in colour).—A dense 
ebony black univalve shell, with rows of very pronounced 
beading running spirally round the whorls. The interior 
is white with a narrow band of pearl just within the outer 
lip and continued round the mouth for about three-quarters 
of its circumference. On the outside surface may be seen 
occasionally a few spots of yellow which give the shell the 
appearance of having been carved out of a solid piece of 
tortoise shell. The whorls are not very distinctly marked 
off from each other, and the base of the body whorl, being 
more or less flat, and angular at the outer border, the entire 
shell takes the form of a flattened cone. It is not common, 
and attains a diameter of half an inch or more. [ound 
25 
Plate VI 
No. 9 
Plate VI 
No.6 
Sea Shells 
of New Zealand 
