New marine mollusca.

TASMANIAN MARGINELLAS.
Tenison Woods when describing M. cyprseoides in these Proceedings for 1877 remarked, "Tasmania is already rich in this genus." If such could be said when the number of species known here was less than, a dozen, how much more may it be emphasised when the total, with those I am now describing, amounts to some 40 species? Recent dredgings in our deeper waters, from 40 to 100 fathoms, have brought to light a great number of new forms, some of which are very distinct species, whilst others vary so greatly in both form and size as to make them exceedingly puzzling. The present paper is an attempt to bring some order out of chaos, and will narrow the work down considerably. In dealing with such a variable group it cannot be hoped that my present work will be final; future discoveries and a larger amount of material may show some of the species to be varieties only. On the other hand some, which I now pass as varieties, may yet be established as good species.