KO. 2207. WEST AMERICAN MELANELLID MOLLVSKS—DARTSCH. 309 

 MELANELLA (MELANELLA) MONICENSIS, new species. 



Plate 36, fig. 2. 



Shell elongate conic, with perfectly straight-sided spire, yellowish- 

 white, polished, marked by fine lines of growth only. Whorls 

 decidedly flattened, suture very poorly defined. Periphery of the 

 last whorl decidedly angulated. Base short, well rounded. Aper- 

 ture rhomboid, with a decided angle at the junction of the outer and 

 basal lip; posterior angle acute; outer lip thin, inner short, straight, 

 revolute; parietal wall covered by a thin callus. 



The type and another specimen (Cat. No. 251301 U.S.N.M.) come 

 from the Upper San Pedro series at Santa Monica, California. The 

 type has lost the early whorls, the 11 remaining measure — length, 

 8 mm., diameter, 2.9 mm. Three additional specimens from the 

 same locality are in Mr. Arnold's collection. 



MELANELLA (MELANELLA) NECROPOLITANA, new species. 



Plate 36, fig. 3. 



Shell moderately large, elongate-conic, slender, with perfectly 

 straight-sided spire. First two whorls moderately rounded, sepa- 

 rated by well marked suture, the remaining flattened, with scarcely 

 impressed suture. Periphery of the last whorl angulated. Base 

 moderately long, well rounded. Aperture oval; posterior angle 

 acute; outer lip angulated at the junction of the outer an({ basal lip; 

 inner lip oblique, curved, slightly revolute, reflected over and ap- 

 pressed to the base posteriorly; parietal wall covered with a thin 

 callus. 



The type (Cat. No. 251314, U.S.N.M.) comes from Sand Rock, 

 Lower San Pedro Series of Dead Mans Island. California. It has 13 

 whorls and measures — length, 7.5 mm.; diameter, 2 mm. 



MELANELLA (MELANELLA) OLDROYDI, new species. 



Plate 36, figs. 5, 6, 7. 



Shell rather broadly elongate-conic, bluish-white in the living 

 form, yellowish-white in the fossil, polished, marked by exceedingly 

 fine lines of growth only. The first three whorls well rounded, 

 separated by a moderately impressed suture; the succeeding flattened, 

 separated by a feebly defined suture. Periphery of the last whorl 

 weakly angulated. Base short, well rounded. Aperture oval; 

 posterior angle acute; outer lip angulated at the junction with the 

 basal lip and slightly protracted at the angle; inner lip short, curved, 

 strongly reflected and apprjssed to the base posteriorly; parietal 

 wall covered with a thick callus. 



The type and another specimen (Cat. No. 109641, U.S.N.M.) were 

 collected by Mrs. Oldroyd at San Pedro, California. The type has 14 

 whorls and measures — length, 9.2 mm. ; diameter, 3 mm. 



