dilated, conical, perfoliate with 24 to 30 leaves on each side. Each of the 7 branchial plumes large, spreading and 3- to 4-pinnate. Radula with 33 rows; center naked; with 42 to 49 strongly hooked, denticulate pleural teeth. Com- mon in tide pools. Subgenus Anisodoris Bergh 1898 Archidoris 720 bills MacFarland Noble Pacific Doris Plate 1 6c California. 4 inches in length. Rhinophore stalk stout, conical, the clavus perfoli- ate, with about 24 leaves, and the stalk deeply retractile within low sheaths, the margins of which are tuberculate. Each of the 6 branchial plumes large and spreading, 3- to 4-pinnate. A thin, membrane-like expansion joins the bases of the plumes. Radula with 26 rows; center naked; with 55 to 62 strongly hooked pleural teeth. Moderately common in tide pools. Genus Discodorts Bergh 1898 Body rather soft, oval in outline; branchial aperture slightly crenulate, stellate or bilabiate; anterior margin of the foot bilabiate, the upper lip more or less notched. Discodoris heatbi MacFarland Heath's Doris Plate i6i California. I inch in length. Mantle thick, densely spiculate. Rhinophores cylindro- conical, the stalk stout, the clavus with 10 to 15 leaves, and wholly retrac- tile. Each of the 8 to 10 branchial plumes are tripinnate. Radula colorless, with 20 rows of teeth; center naked. 36 to 42 strongly hooked pleural teeth. Rather rare in rock pools in the summer. Genus Rostanga Bergh 1879 Back covered with minute, spiculose or stiff papillae; branchiae of simple-pinnate leaves. Rostanga pulchra MacFarland MacFarland's Pretty Doris Plate i6g California. % inch in length. Rhinophores short, stout, translucent-pink, stalk stout, prolonged beyond the 20- to 24-leaved clavus as a blunt, cylindrical process which is % the length of the entire rhinophore. 10 to 12 erect, sepa-
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American Seashells
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