234 
LIMN^AD^; 
mantle a blood-red fluid similar to that of Aplysia in 
appearance. 
Shell an inch in diameter, thick, black, or of a 
rusty brown colour, obliquely striate ; volutions five, 
the outer one rounded with a deep umbilicus on the 
under or front side, exposing three of the volutions ; 
upper surface a little concave and whitish ; aperture 
rather oblique, rounded, as high as broad. 
b. Shell concave above; whorls crested or ciliated; 
mouth roundish, (Gyraulus.) 
104. 2. Planorbis albus. White Coil Shell. 
Shell thin, pellucid, white, concave, and with 
the whorls equally convex on both sides, with 
fine raised hispid spiral striae ; mouth round- 
ish-rhombic. (t. 8. f. 97.) 
Planorbis albus. Muller ^ Verm, ii. 164. ; Leach^ Syn, Moll, 
113. ; Jeffreys,, Linn, Trans, xvi. 387.; Turt, Man, ed. 1. 
114. f. 97. ; Forhes and Hanley,^ B, M, iv. 149. t. P26. f. 1, 2. 
— Helix alba. Mont, p. 459. t. 25. f. 7. — Planorbis hispi- 
dus. Brap, Hist, p. 43. t. 1. f. 45 — 48.; Brard,, p. 159. t. 6. 
f. 6, 7.; Lam, Moll. vi. 154. — Planorbis villosus. Poiret., 
Prod, — Planorbis hirsutus. Gould,^ Inv, Mass, 206. f. 138.? 
— = Gyrulus hispidus. Hartm, Gast, t. 25. 
In stagnant waters, on aquatic plants. 
Animal greyish, (^Sturm, t. 42.) 
Shell about a quarter of an inch in diameter, very 
thin and brittle, pale horn-colour, marked with very 
fine close-set raised circular striae, which are clothed 
with deciduous bristles, and crossed with obscure 
longitudinal lines ; volutions five, the first very large 
and rounded ; the upper surface a little sunk in the 
middle, the under side more strongly concave ; aper- 
