tures which recall that genus being evidently adaptive in both groups. I should suspect a relation to Capulus—that is, that it might be some form of Capulus which had taken to living inside shells, as the unguiformis (Janacus) type of Crepidula has done. I have described, under the name of Hyalopatina, a curious shell which recalls this, but has a more central nucleus. I took it to be related to Umbrella, or something of that sort, but have only the one specimen without the animal. It is finely radiately sculptured, and nearly flat. Whether this and your shell are nearly related I cannot pretend to say, but conchologically there are points of resemblance. You will find Hyalopatina figured on plate 30, fig. 5, of Proc. U.S. Nat. Mus., No. 1264.” The shell was described by Dr. Dall as Hyalopatina rushii. ^*

Fresh specimens of our shell show a dextral spiral smooth protoconch, and a horse-shoe-shaped muscle-scar. The surface is concentrically striated, but there is no radiate sculpture. For this new shell I propose the generic name Neojanacus, and place it in the family Capulidœ. I need hardly say that for the present the diagnosis of the species must also be that of the genus. It is to be hoped that the anatomy of the two conchologically related genera Hyalopatina and Neojanacus may be investigated some day, and their true systematic position settled.

Type (from 110 fathoms, off Great Barrier Island) in the Colonial Museum.