NOMENCLATURE. 15 



sci'oltculati. Furrowed ; covered with little fur- 

 rows or excavations. 



scripti. Lettered ; marked with various charac- 

 ters resembhng letters. 



sinisiri. Left-handed, heterostrephous, turn- 

 ing round the pillar from right to left, in- 

 stead of pursuing their usual, opposite, 

 course. 



spinoso^radiaii, Spinosely radiate; beset with 

 spines in a circle, either concatenate, 

 united at their bases, or setaceous^ like 

 bristles. 



striati. Striate ; encompassed with very fine 

 raised or excavated lines : punctate striae 

 are those which have elevated or impressed 

 points placed along them ; the points 

 may be concatenate, strung like beads, or 

 pertuse, deeply excavated. 



sulcati. Sulcated; marked with broader lines, 

 either hollow, ridged, or elevated. 



Apertura. Aperture, mouth; the orifice, en- 

 trance, or opening of the shell. 



himarginata, Bimarginate ; having the lip with 

 a double margin. 



