70 Mr. E. A. Smith on some new Eatonia, gen. nov. Testa forma? rissoidese ; apertura subcireularis ; peristoma simplex, continuum, margine labrali haud inerassatum. Operculum ovatum, pauci-vel unispirale, nucleo subterminali a latere columellari paululum remoto, infra ossiculo prominenti a nucleo exsurgente et versus marginem columellarem extenso munita. There are two genera which have affinity to the present one — Jeffrey sia and Rissoina. With Jeffrey sia it agrees in the form and character of the aperture, but differs in having the nucleus of the operculum not lateral, but situated within the margin and towards the lower end — in fact, agreeing in this respect with Rissoina (see Adams, ' Genera of Recent Mollusca,' vol. iii. pi. 35. f. 1, a& b), but distinguished from it by the absence of the basal faint channel of the aperture and the lack of any incrassation to the labrum. The operculum of Jeffreysia is composed of concentric layers (as in Purpura), commencing from a nucleus situated on the margin of the inner or columellar side ; and the ossicle or rib proceeds "from the nucleus in the direction of the outer margin " (Jeffreys, ' Brit. Conch.' iv. p. 58 ; in the figure, I.e. pi. 1. f. 3, it is apparently the reverse). In Eatonia the operculum is spiral, consisting of one or more whorls, the nucleus is situated within the margin and about one fourth the entire length from the lower end, and the ossicle is directed towards the inner margin. I feel much pleasure in associating with this group the name of the Rev. A. E. Eaton, who worked so indefatigably in collecting specimens during the expedition. 6. Eatonia Jeerguelenensis, sp. nov. Testa ovato-conica, tenuis, olivaceo-nigrescens, versus labrum palli-dior semipellucida, vix rimata ; anfractus 6, convexi, lseves parum nitidi, incrementi lineis striati, sutura simplici sejuncti ; apertura fere circularis, longitudinis totius ■& aequans ; peristoma simplex, continuum, in regione umbilicali leviter inerassatum et vix reflexum. Operculum ovatum, intus concavum, nucleo posteriore sed haud ter-minal^ crassiusculum, margine externo lira inerassatum, unispirale, supra incrementi lineis vakle striatum, infra ossiculo elongato a nucleo exsurgente munitum. Long. 3 mill., diam. 1^. Hob. On a sponge, Kerguelen's Island. This species was found in company with Rissoa Kergueleni. It is of a very different form, the spire being conical, the last
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