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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 yellowish 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 1¾ inches long. The right valve is rounded and the left 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 3½ inches across, and is found on sandy ocean beaches all over New Zealand. The Maori name is Kuhakuha.
MACTRA ÆQUILATERA (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 VIII.).
STANGELLA 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.
