210 
rough, spinous, or tubereulated varices ; aperture 
rounded or oval; varices at least three, the lower 
uniting obliquely with the upper in longitudinal 
series ; a horny operculum. 
M. Errinaceus. Lin. 1216.—D. p. 690.—Lam. 48. 
—Macgy. Aber. p. 168.—Knorr. 4. t. 23. f. 3.— 
Born. t. 11. f. 3,4.—Pen. 4. p. 123. €. 76. f. 95.— 
Don. t.35.—Mont. p. 259.—Dor. Cat. ¢. 14. f. 7.— 
(Da Cos. t. 8, f. 7.)—Triton E. F. p. 356.—Oval- 
oblong, rough, strong,angnlated, dirty white or brownish, 
with seven or eight produced and contabulated whorls, 
the apex pointed ; whorls with six or seven rugged pro- 
minent varices, crossed by transverse elevated strie, the 
whole shell (when not worn) imbricated by small 
arched scales ; aperture oval, canal tubular, outer lip 
thickened by a rib, inner edge dentated. 14...0,80. 
Common. 
Tripe.—ALATA. 
With a longer or shorter canal at the base of the aper- 
ture ; outer lip changing its form by age and sinua- 
ted below. 
GrENuS.—ROSTELLARIA. 
usiform or subturreted, terminating below in a beaked 
canal ; outer lip dentated or entire, more or less 
