NERITA. NERITE. 127 
7 Nerita fluviatilis. River Nerite. 
Lister, pi. 141. f. 38, and pi. 607- f. 43,44 — Pennant, 
pi. 90. f. 2— Da Costa , pi. 3. f.|8— Donovan, pi. 16*. f. 2— 
Dorset Cat. pi. 16. f. 17, 18. 
Shell somewhat oval, semitransparent, often covered 
with a greenish or brownish skin, slightly wrinkled across, 
variegated with purplish-brown, white, pink, or pale brown, 
in spots, streaks or bands : spires three, the first volution 
very large and produced at the outer-lip 3 the others small 
but well defined, placed laterally, and ending in a fine point : 
aperture half-moon shaped 3 the outer lip thin ; pillar-lip 
white, polished, broad, with an acute entire edge: diameter 
three-eighths of an inch. 
In slow rivers, v. v, 
8 . Nerita tuberosissima. Tubcrcled Nerite. 
Montagu, pi. 29. f. 5. 
Shell white, transparent, somewhat orbicular, with a 
very minute point: spires three or four; the first very 
large, and marked with four circular tubercled ridges 3 the 
others very small and lateral: perforation large : diameter 
about the eighth of an inch. 
Firth of Forth: very rare. 
9. Nerita pellucida. Linn. Trans, iii. p. 67. 
Shell smooth, transparent, with three volutions : mi¬ 
nute. 
On the Pembrokeshire coast. 
10. Nerita alba. Linn. Trans, iii. p. 67- 
Shell smooth, semitransparent, with two volutions : mi¬ 
nute. 
On the Pembrokeshire coast. 
B. With the pillar-lip toothed, 11. 
11. Nerita vbginea. Spotted Nerite, 
Lister, pi. 606, f. 35 to 37- 
Shell oval, smooth, polished, white with a pale ferrugi¬ 
nous tinge, elegantly marked with black zigzag lines run¬ 
ning, in various directions : spires three or four, hardly di¬ 
stinguishable from each other, with a blackish line running 
roynd the junctions, and a little carious at the tip : aper¬ 
ture 
