leaves, all told, in the club of the rhinophore. Distinguished from frondosus by the 3 to 5 small but well-marked dendriform papillae on the posterior edge of the rhinophore sheath. Usually dredged down to 25 fathoms. Prob- ably the largest of the American nudibranchs. Fa7mly SCYLLAEIDAE Genus Scyllaea Linne 1758 Scyllaea pelagic a Linne Sargassum Nudibranch Southeast United States. Other warm seas. I to 2 inches in length. Translucent cream-brown to orange-brown. With numerous flecks of red-brown. Body elongate. Oral tentacles absent. Two slender long rhinophores. Sides of body with 2 pairs of large, club- like, foliaceous gill plumes or cerata. Common in floating sargassum weed in the Gulf Stream. Family AEOLIDIIDAE Genus Aeolidia Cuvier 1798 Body depressed, rather broad; branchiae a httle flattened, set in numer- ous, close, transverse rows; 4 tentacles simple; foot broad, anterior angles acute. Radula of a single, broad, pectinate plate, Aeolidia papulosa Linne Papillose Eolis Plate i5g Arctic Seas to Rhode Island. Europe. Arctic Seas to Santa Barbara, California. I to 3 inches in length. Color variable: brown, gray or yellowish, always more or less spotted and freckled with lilac, gray or brown and opaque-white. Number of papillae fcM^er in young specimens. 30 rows in radula of a single, broad, arched tooth bearing about 46 denticles. Family TERGIPEDIDAE Genus Catriona Winckworth 1941 (Cratena of authors) Catriona aurantia Alder and Hancock Orange-tipped Eolis Plate 15J Arctic Seas to Connecticut. Europe. % inch in length. Branchiae numerous, occurring in 10 or 11 close, transverse rows, anteriorly with 5 to 6 papillae per row, posteriorly with 2
