216 



Scalaria — continued. 



decussata — turreted ; long, transversely striated ; ribs longitu- 

 dinal ; whirls contiguous — f inch. 



denudata. . turreted, ribs few, whirls distant — f inch. 



monocycla. . conical, whirls contiguous, a raised stria on the 

 base of the last turn — f inch. 



plicata. , turreted, small plicse-formed ribs. 



Turritella. 



imbricataria. . subulated ; whirls flat, imbricated, transversely 



striated, finely granulated intermediately — 3 inches. 

 sulcata. . conical, transversely sulcated, lowest grooves deepest, 



fine vertical bowed stride — 2 inches. 

 subcarinata. . conical, transversely sulcated, grooves unequal, 



separated by keels — 1 inch. 

 fasciata. . conical ; two grooves in the upper part of the whirls; 



a flat zone in the middle divided by a fine striae — f inch. 

 multisulcata. . conical, whirls convex, numerous ; nearly equal 



grooves — 1 inch. 

 tet'ebellata. . long, subulated, whirls subconvex, striated, with 



small interstitial whirls — 5 inches. 

 perforata. . subulated, whirls flat and imbricating, with three 



transverse striae and a raised margin ; columella perforated 



through its whole length — 1 inch. 

 unisulcata. . subulate ; smooth flat whirls, one groove at the 



lower margin — 1 inch. 

 uniangularis. . conical, subulate, one transverse angle in the 



middle of each whirl — | inch. 

 melanoides. . conical, whirls flat with transverse striae and 



grooves intermixed — i inch. 

 There exist numerous varieties of these species. 



Bulla. 



ovulaia. . transversely striated, spire involved — | inch. 

 striatella. . short, finely striated ; spire obtuse, upper edges of 



each whirl carinated — small. 

 cylindrica. . striae chiefly on the base, vertex umbilicated — | inch. 

 coronata. . oblong, subcylindrical vertex umbilicated, the margin 



coronetted. 



Bulimus. 



albidus. . ovate, smooth, whirls rather convex ; opening semi- 

 ovate. Seems not to be fluviatile — § inch. 



citharellus. . ovate conical ; transversely striated, longitudinal 

 ribs, apex papillated — very small. 

 Marine ?. . Auricula ? 



tei^ebellatus. . turreted, umbilicated, very smooth, opening oval, 

 angular at both sides — f inch. 



acicularis. . turreted, long, thin — small. 



nitidus. . turreted, very smooth, whirls rather convex, lip sharp 

 . . small. 



