33 
shell gapes to a considerable extent at the narrower end. It is 
found in the open sea in sand in the North Island, Cook Strait, 
and Australia. 
CORBULA ZELANDICA (Plate VIII.).—Fig. 5 is a yel- 
lowish or pinkish-white shell, with fine longitudinal lines on it. 
The interior is brownish, and the shell over half an inch long. 
It is common in the North Island and Australia. 
SAXICAVA ARCTICA (Plate VIII.).—Fig. 6 is a rough, 
distorted, yellowish-grey shell, about three-quarters of an inch 
long. The interior is whitish. It is usually found in the roots 
of kelp or in sponges, and is obtained in both Islands. 
MYODORA STRIATA (Plate VIII.).—Fig. 7 is a whitish 
or greyish-white shell, with fine longitudinal lines, the interior 
being pearly. It is 12 inches long. The right valve is rounded 
and the teft valve flat. It is found in harbours, as well as on 
ocean beaches. The flat valves make excellent counters for card- 
players. 
MYODORA BOLTONI (Plate VIII.).—Fig. 8 is a smaller 
and narrower shell than the Myodora striata, and the left valve 
is flat. In colour it is similar to the Striata. It is seldom over 
half an inch long, and lives on flat, sandy beaches. It is often 
found when sifting sand for small shells through a fine meshed 
sieve. 
MACTRA DISCORS (Plate VIII.).—Fig. 9 is a large, 
rotund, greyish-white shell, with a blackish-brown epidermis. It 
is over 34 inches across, and is found on sandy ocean beaches all 
over New Zealand. The Maori name is Kuhakuha. 
MACTRA AQUILATERA (Plate VIII.).—Fig. 10 is a 
yellowish or white shell. It generally has a bluish-purple patch 
round the hinge. It is found on ocean beaches, and is over two 
inches long. The Maori name is Kaikaikaroro, which is also 
used for the Struthiolaria (Plate IV.), and Chione costata (Plate 
WELT’). 
STANDELLA OVATA (Plate VIII.).—Fig. 11 is a thin, 
brownish-white, and somewhat wrinkled, shell over three inches 
long. The edge of the shell, and sometimes the whole shell, is 
covered with a brownish epidermis, the interior being yellowish. 
This shell is found all over New Zealand on muddy beaches, and 
especially near mangrove bushes in Auckland Harbour. 
