195 
straight canal; base with two or three smooth spiral 
ridges. ¢...0,01L1. Sheerness and Devon. 
Genus.—PLEUROTOMA. 
Turreted or Fusiform ; terminating below in a more or 
less elongated and straight canal; outer lip with a 
transverse fissure or notch near the suture. 
P. Graciuis. F. p. 354.—Muvrex G. Mont. p. 
267. and Sup. p. 586. t. 15. f. 5.—D. p. 742.—Lin. 
T.8. p. 143.—Dor. Cat. p. 46. t. 14. f. 18.—M. 
Emarcinatus. Don. t. 169. f. 2.—Slender, tapering 
to a fine point, yellowish with lighter and brown bands ; 
whorls little rounded, with eleven or twelve very convex, 
obtuse longitudinal ribs interrupted at the suture by a 
depressed spirally striated space, the spiral strize at the 
base strong and rather distant ; aperture oval, canal mo- 
derately long, rather open. %...¢. Deep water, not 
uncommon. 
P. Sinvosa. &. p. 354.—Murex 8. Mont. p. 264. 
t. 9. f. 8.—Ian. T. 8. p. 145.—D. p. 745.—Strong, 
thick, white; whoris six, tapering to a fine point, little 
convex, with seven longitudinal, strong, much elevated 
and arched ribs which do not extend to the fine suture, 
finely and regularly striated transversely, the striae most 
conspicuous in the interstices; aperture narrow and 
i 2. 
