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240 Nassarius mendicus Gould Western Lean Nassa Figure 53d Alaska to Lower California. % to % inch in length, with a moderately high spire. Outer lip not thickened. Sculpture consists of numerous, small beads which are formed by the crossing of about a dozen small axial ribs and smaller spiral threads. Color yellowish gray. Common in shallow water in the north. The subspecies or form cooperi Forbes has weaker spiral threads and about 7 to 9 strong, whitish, smoother axial ribs which persist to the last of the body whorl. Color grayish yellow to whitish, often with fine, spiral, brown or mauve lines. Very common in the south. Subgenus Zaphon H. and A. Adams 1853 Nassarius fossatus Gould ^ Giant Western Nassa Plate 20s Vancouver Island to Lower California. I V2 to 2 inches in length, orange-brown to brownish white in color. Early whorls coarsely beaded; last whorl with about a dozen coarse, variously sized, flat-topped spiral threads and with about a dozen short axial ribs on the top third of the last whorl. Outer lip with a jagged edge and constricted at the top. The largest and one of the common intertidal Nassa snails on the Pacific coast. Subgenus llyanassa Stimpson 1865 Nassarius obsoletus Say Eastern Mud Nassa Plate 23P Gulf of St. Lawrence to northeast Florida. Introduced to the Pacific coast. /4 to I inch in length, usually covered with mud and algae, and has its spire eroded at the tip. Color dark black-brown. Sculpture of numerous rows of weak beads. Parietal wall thickly glazed with brown and gray. Columella with a single, strong spiral ridge near the base. Outer lip with half a dozen small grayish teeth which run back into the aperture. Very common on oozy, warm mud flats. Family FASCIOLARllDAE Subfamily FASCIOLARIINAE Genus Leucozonia Gray 1847 Leucozonia nassa Gmelin Chestnut Latirus Plate 1 1 1! Florida to Texas and the West Indies.