Collonia, _Gray_, (hodie) = Collonia, _Add._, but not Collonia, _Gray_, (olim). Of the species arranged by Mr. H. Adams under Collonia, some may belong to the original genus: some are included under Cynisca, _A. Ad._; and one (Turbo phasianella, _C. B. Ad._) appears to be Eucosmia. They appear in the Br. Mus. Col. distributed between Gibbula and Photinula. The true Turbo marginatus of Nutt. is the ordinary black Californian Chlorostoma, like mœstus, and well named from its frilled margin near the suture. But the label having become affixed to the T. marginatus _Rve._ (which must stand as Reeve’s species and not Nuttall’s) the Californian shell was left without name, and was described by Mr. A. Adams as Chl. funebrale, under which name it must stand as Nuttal’s prior name was (unfortunately) in MS. only. The name Collonia marginata must stand for the original fossil of Lamarck. It is probable that Reeve’s shell belongs to another group; else it must, according to the usual custom of honoring error, be called C. Reevei. For the Californian species, which are imperforate and have a thin, smooth operculum, Mr. A. Adams and I propose to form a subgenus _Leptonyx_; a diagnosis of which will appear in the next paper, after the foreign species have been examined. The following are the Californian forms. _Leptonyx sanguineus_, Linn. H. t. parvâ, solidâ, rubrâ, anfr. V. subtumentibus, suturis plus minusve impressis; costulis spiralibus plus minusve rotundatis cinctâ, quarum iv.-viii. in spirâ monstrantur; aperturâ subcirculari; columellâ t. adolescente foveâ basali et dente ut in ‘Modulo’ munitâ; adultâ, callositate tenui labiali, foveam tegente, obscure bidentatâ; labio tenui, continuo; umbilico nullo. _Hab_. Mediterranean, _Phillippi_, _Hanley_. Japan, _A. Adams_. Monterey, _Jewett_, _Taylor_, _Cooper_. Neeah Bay, W.T., _Swan_. = Turbo sanguineus, Ln. Syst. Nat. Ed. 12, p. 1235:—Phil. Moll. Sic. in loco: Hanl. Ips. Lin. Conch, in loco. = T. Belliæi, Michaud in Mus. Paris: teste Hanl. Non “Turbo sanguineus, Linn.” Rve. Conch. Ic. sp. 55: = T. coccineus, _Desh._ = Globulus roseus, Chem. teste Rve. Nec (Gibbula) sanguinea, _Risso_.