APLEXUS. 
229 
shell is longer^ and the inner lip parallel to the 
outer^ and not spread over the body whorl. 
Adanson first described this genus in 1757, under 
the name of Bulin (Bulinus), which ought to be 
adopted ; but it would create confusion, as Hartmann 
and Mr. Broderip have lately changed Lamarck’s 
genus Bulimus^ which is synonymous with Cochlea 
of Adanson, into Bulinus. 
102 . 1. Aplexus Slender Aplexus. — Shell 
horn-colour, oblong, with an elongate pointed 
spire; aperture oval-lanceolate, (t. 9. f. 113.) 
Bulla hypnorum. Linn, S, N. i. 1182. ; Mont. p. 228.~Buli- 
mus hypnorum. Brug, Ency, Meth. 301. — Planorbis 
turritus. Muller.^ Verm.W. 169. — Physa hypnorum. JDrap, 
Hist. p. 55. t. 3. f. 12, 13.; Turton, Man, ed. 1. 129. f. 113.; 
Forbes and Hanley., B, M. iv. 143. t. 122. f. 6, 7. — Bulla 
rivalis. Flem. Ed, Ency. vii. 85. — Limnea turrita. Gray., 
m So^cerby., Gen, f. 10. — ISTauta hypnorum. Leach, Syn. 
Moll. 110. — Helix marmorata. Gmel. S, N. 3665. — Aplexa 
hypnorum. Fleming, B. A. 276. — Aplexus hypnorum. 
Gray, Man, 255. 
In ponds and slow streams. 
Animal blackish ; foot quite as long as the shell ; 
tentacles black. 
Shell half an inch long, and a third part as broad, 
dark horn-colour, glossy and transparent ; spire com- 
posed of five or six produced and hardly raised volu- 
tions, ending rather acutely ; aperture narrow-oval, 
covering about half the shell ; the pillar a little sinu- 
ate, often of a pale rose-colour. 
The eggs are deposited in oblong masses exactly 
similar to those of LimruBus, slightly attached to shells 
and water-plants. (See Pfeiffer^ t. 7. f. 24. 27.) 
