nch across, and is usually found near half-tide mark in
harbours. The exterior is covered with black or bluish irregular bands.
The interior is nacreous, and of a greenish colour, with a white patch
round the columella.

~MONODONTA AETHIOPS~ (Plate VI.).--Fig. 12 is a purplish-black shell,
tesselated with white between the grooves. These grooves look like lines
in the plate. The interior of the mouth is white. Besides being usually
covered with vegetable growth, part of which is seen in the
illustration, the point of the spire is frequently worm-eaten and
defective. This is the usual state in which all shellfish that herd
together are found. It is upwards of an inch across, and found in large
numbers amongst rocks, especially at the entrance to harbours, and from
half-tide mark downwards.

~MONODONTA NIGERRIMA~ (Plate VI.).--Fig. 13 has a smooth, purplish-black
exterior, sometimes with small blue spots. The interior is white, and
the shell about half an inch across.

~MONODONTA LUGUBRIS~ (Plate VI.).--Fig. 14 is a thick, solid black shell,
sometimes over half an inch across, and covered with coarse, irregular
granules. The interior is white. This shell is found in large numbers
under stones, at the entrances to harbours and sheltered beaches, almost
up to high water mark.

There are six or seven other Monodonta in New Zealand, but they are
small, and the four above described are the ones most likely to be met
with.

~TURBO GRANOSUS~ (Plate VI.).--Fig. 15 is a reddish-purple shell, varied
with white, and is sometimes over 2-1/2 inches across. The specimen
photographed was much below the average size. The exterior is covered
with well-defined rows of granules, while the interior is iridescent.
It is found on rocks in the open sea in both Islands, but is a rare
shell. The operculum is white and shelly.

~TURBO HELICINUS~ (Plate VI.).--Figs. 16 and 17 (late Turbo smaragdus) is
a blackish-green shell, found in great numbers at half tide mark on
rocks all over New Zealand, especially at the entrance to harbours and
in sheltered bays. Some are as much as 2-1/2 inches across. The inside
is white and glistening. The operculum is a solid, round, shelly one,
with a greenish centre. In some specimens the outer side of the whorl,
instead of being round and smooth, has two or three prominent raised
ribs or bands on it. This variety is called Tricostata, and is
represented by Fig. 16. I am inclined to believe it is only the you