PILEOPSIS. ll 
F. pustuLta. Roundish elliptic, flattish, and 
truncated in front, dirty white, with decussated 
strie ; longitudinal strie rather prominent; per- 
foration not central, lengthened, enlarged in the 
middle, and girded with a pink line; small. W. 
38. 90. 
F. FASCICULARIS. Small, oblong - elliptic, 
flattish, sallow, and rayed with pinkish-brown 
fasciculated lines; striz crowded ; perforation as 
last; internal border apparently entire; nests 
only on its sides. 4. 
F. minuta. Minute, oblong-elliptic, convex, 
white, decussated with slender strize, of which 
the longitudinal are sub-granular, rayed with thin 
black lines; perforations small, not central. 
PILEOPSIS. 
Univalve ; obliquely conic ; anteriorly recurved ; 
summit hooked, sub-spiral ; aperture elliptically 
round ; anterior margin shortest, the posterior 
one large and rounded; the muscular wmpres- 
