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Acmaea cantharus (akme, a point; kantharos, a shallow two-handled tankard, a pot).—A small oval limpet, about half an inch in length, with a thin, comparatively smooth shell, having the apex, which is a hooked beak, situated in the anterior or front quarter. The front of the shell has a concave slope, and the posterior, or hind slope, is a convex one. The sculpture, or external moulding, though more often than not obscured by incrustation, consists of fine concentric growth lines and fine striæ (literally, scratched lines) radiating from the apex; these can only be seen with a good lens. In colour the shell is brownish, flecked with white, and the interior is “light blue, occasionally light brown; central area chestnut brown, the sharp margin often banded or dotted with yellowish brown.” (Suter).

Found at Oamaru; Dunedin; Preservation Inlet; Herne Bay, Auckland Harbour.

Note.—Although this Acmaea has been given a specific name, it is recognised now as the juvenile form of Acmaea Pileopsis. In collecting shells it is always advisable to procure a fair number of them, as the colour variation is likely to prove confusing if you content yourself with a pair only. For instance, in twenty-seven specimens of the Acmaca Cantharus which I obtained from small and sheltered rock pools near high-water mark at Herne Bay, there were only three out of that number that were really blue internally; the others were of an indeterminate blue, one a bluish white, and the remaining twenty ranged from yellowish browns and light browns to purplish browns. The marginal bands also showed considerable variety, the blue interior being bordered with black, the others being for the most part parti-coloured.

Plate V
No. 9

Acmaea daedala (akme, a point; Daedalus, a mythical Greek sculptor).—A small oval limpet of a pale yellowish colour, marked with a network of fine brown lines. The apex is pointed and curved forward. The