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Rh stricted. There is only one species in the genus. The genera Cuvieria Rang and Herse Gistel 1848 (non Oken 181 5) are synonyms. Cuvierina columnella Rang Cigar Pteropod Figure 64m Worldwide, pelagic. (43° N. to 42° S.). 10 to 14 mm. in length. See generic description and figure. The shell varies somewhat in shape. C. oryza Benson, C. iirceolaris Morch and cmi- cellata Pfeffer are the same. Common. Suborder GYMNOSOMATA Pteropods characterized by the absence of shell, pallial cavity and mantle-skirt; by the presence of a well-developed head, bearing two pairs of tentacles, of which the two posterior bear rudimentary eyes. Jaws and radula present. Found pelagic in all seas, and sometimes in great abundance. Rarely exceed one inch in length. They are carnivorous. Ascend to the surface at night, and sink to a lower level in the daytime. They are not treated in this book. The group contains such genera as Pjieuviodennopsis Bronn 1862, Fneumodernia Cuvier 1805 {=^ Piieiimono derma Agassiz), Cliopsis Troschel 1854 {= CHonopsis Bronn), Notobrmichaea Pelseneer 1886, Clione Pallas 1774, PaedocUone Danforth 1907, Anopsia Gistel 1848 (= Halopsyche Bronn and Euribia Rang). Order NUDIBRANCHIA (Nudibranchs and Sea-slugs) Super jamily DORIDACEA Family DORIDIDAE Branchial plumes in an arc or circle usually joined together at their bases, usually retractile into a cavity. Rhinophores always with a perfoliate club. Pharyngeal bulb never suctorial. Genus Archidoris Bergh 1878 Body not hard, dorsum granular or tubular; tentacles short, thick, with an external, longitudinal sulcus. No labial armature. Branchial plumes not numerous, 3- to 4-pinnare. Center of radula naked, marginal teeth hooked and bearing minute denticles. Penis and vagina unarmed (without hooks). Archidoris montereyensis Cooper Monterey Doris Plate i6h California. I to 2 inches in length. Rhinophore stalks conical, the clavus slightly