PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 45 Table showhif/ Comparative Projwrtions of Atlantic Species of Caulolatilus. 46 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.Body rinj?s, 1 + 10. Caudal rings, 37. Tubercles of body and tailoloDgated, slightly recurved, usually prolonged into slender filaments;those on the 2d, 4th, and Gth body rings much larger than the others;tubercles prominent and filamentose upon the 4th, Gth, 9th, 12th, IGth,nud 20th caudal rings. Ventral tubercles upon Gth, 7th, 8th, and 9thbody rings. Occipital crest very high, with live prominent tubercles,the anterior two with long filaments. Length of snout equal to dis-tance from posterior margin of orbit to gill-opening. Operculum markedwith fine, radiating strine.Radial formula.?D. 19 (the first imperfect). P. 18. V. 4.Color.?Yellowish-brown; the eyes and cheeks covered with radiating,wavy lines of light brown. Snout encircled by a narrow, undulating,white band near its middle.The Commission has an accurate sketch by Mr. Emertou.April 30, 1878. ?ESCKIB>TIO.>'.?( OF NEU' SPECIE!^ OF MHEI.I.S FROITI ?Ar.IFORNIAi.\ Tin; c oi.i-iErTio:v.s of the natsoivai. miseijiII.By W. II. OALL.Haliotis (.'var.) assimilis, u. s.Shell solid, strong, not very thick, with a rather light piuk, white andgreenish nacre, usually with five open holes ; spire more elevated thanthat of any other Californiau species, consisting of two and a half orthree whorls; aperture very oblique in adult specimens, the thickenedmargin of the columella narrow, somewhat concave, inclined sharplyinward and upward, about three-fourths as long as the columellar side,of the aperture. Between the row of openings and the columellar edge,the space is unusually broad, marked midway by an obtuse carina, sep-arated from the row of holes by a shallow channel; surface reddish ordull greenish, with rather rough, crowded, unequal, spiral ribs androunded, irregular, wavy, radiating undulations crossing the spiralsculpture obliquely. The muscular impression, in most specimens, isbut lightly marked, and, except for occasional spot-like impressions, issmoothly nacreous, like the rest of the interior. Lon. 4.5 in. Lat. 3.0in. Alt. of spire 1.5 to 2.0 in. Aperture 3 inches wide and 3.75 long,in an adult specimen.Hah itat?Monterey ; S3H Diego, Ciil.; in deep water only; thrownup by heavy storms, usually dead and worn when found and everywhererare. Mus. Cat. 31267.This species, or variety, has long been knowu to me and to mostCaliforniau collections, but has not hitherto been characterized, owingfo the dead condition of most of the specimens found. Mr. Hemphillhaving forwarded two fresh specimens, it seems well to put it on record.The form is different from any other Californiau species; the spiral