ABSTRACT
Platylepas, moreover, when all its characters are considered, has as good a claim to be generically separated from Coronula, as has Tubicinella a genus universally admitted. The walls of the shell in Platylepas bissexlobata are permeated by minute pores, and have exactly the same structure as in Coronula; the pores being completed by the union of ledges on the outer sides of the longitudinal septa, and the latter have little knobs formed on them at each period of growth. In Platylepas decorata the walls are solid. The Platylepas bissexlobata ranges from the Mediterranean and west coast of Africa to the West Indies, to the north-east coast of Australia, and, judging from the name given by Chenu, to California: the second species, Platylepas decorata, inhabits the Pacific Ocean; and the third imperfectly known species, was deeply buried in the skin of a sea-snake, off Borneo.
