GLYPHIS. 215 



G. densiclathrata Reeve. PI. 39, fig. 86. 



Shell oval-oblong, elevated, perforation at about the front third 

 of the length, front slope straight, posterior slope convex ; sculp- 

 tured with very numerous narrow subequal riblets, beaded at their 

 intersections with the fine concentric elevated stria?. Hole small, 

 oval. 



The beads on the riblets are rounded, but irregularly developed 

 on different shells. The interior is white, hole-callus white, slightly 

 truncated behind, sometimes encircled by a brownish rim. Edge 

 finely crenulated ; basal side-margins scarcely arched, nearly level ; 

 posterior end of the short-oval hole scarcely more elevated than the 

 front end. The surface is lusterle.ss, dull grayish with blackish 

 stripes. Length 16J, width 10, alt. 7 mill. 



Santa Barbara, San Diego, etc., California. 



F. densiclathrata Rve., Conch. Icon. f. 64, 1850. 



G. in^qualis Sowerby. PL 34, fig. 63. 



Shell oblong,'narrower in front, rather depressed, the front slope 

 about half the length of the posterior slope ; sculptured with close 

 fine subequal radiating riblets, crossed by still closer elevated con- 

 centric threads. Perforation about three times as long as wide, about 

 one-seventh the length of the shell. 



Inside white or having dark rays, rings or patches, the hole-cal- 

 lus wide, very distinctly truncated behind. Riblets of the outer sur- 

 face visible as ivhite radiating lines within. Side-margins arched, so 

 that the shell rests upon the ends alone. Color yellowish or gray- 

 ish, rayed with dull black. Length 27, width 16, alt. 7-8 mill. 



San Ignacio Lagoon, Loiver California ; Mazatlan. 



F. incequalis Sowb., P. Z. S. 1834, p. 126 ; Conch. Illustr. f. 45.— 

 Reeve, Conch. Icon. f. 50.— F. pica Sowb., P. Z. S. 1834, p. 126; 

 Conch. Illustr. f. 32, 33. — Rve., Conch. Icon. f. 49. — Glyphis ince- 

 qualis Sowb., Carpenter, Mazat. Catal. p. 220. 



The extreme forms of this species are very dissimilar. Typically 

 it has the hole very near the front margin, and long, narrow, tri- 

 lobed ; other specimens have a rounder hole, much nearer the mid- 

 dle of the shell. 



Var. pica Sowb. PI. 34, fig. 64. 



Perforation short-oval, nearer the center. 



