NERITINA. 47 



il. 194. ; Brap. p. 31. t. 1. f. 1 — 14. ; Brard, p. 194. t. 7. f. 

 9. 10. 12. ; Mont. p. 470. ; Turt. Did. 127. ; Forbes and 

 Hanley, B.M. iii. 3. t. 71. f. 1. 2. t. H. H. f. 1. — Nerita 

 fontiiialis, Brard, Coq. Par. 196. t. 7, f. 11. — Neritina 

 zebriiia, N. peloponnensis. N. numidica, N. Mittreana. 

 Recluz. — Neritina intexta. Villa. — Neritina Sardon and 

 N. trifasciata. Menhe. — Neritina Hildreichii. Schiverz, 



— Nerita Bourguignati. Recluz., Jour. Conch. 1823, 293. 



— Nerita Prevostiana, Pfeiffer, D. Moll. iii. 49. t. 8. f. 11, 

 12. — Nerita thermalis. Boubee in Bull, ]833, 12. — Theo- 

 doxus lutetianus. De Montfort, ii. p. 351. — Neritina 

 fontinalis. Brard, Hist. C. 196. t. 7. f. 11. 13.; Pet. Gaz. 

 t. 91. f. 3.; List. Conch, ii. 1. 38. ; Sivamm. B. N. 80. t. 10. 

 f. 2. — Neritina dalmatica. Sow. C. Illus. f. 57. — Neritina 

 variabilis. Hecart. Moll. Vail. 1. 146. 



In sloAV rivers, adhering to stones. 



Animal white ; head and back of the neck blackish ; 

 hinder part of the foot sometimes black spotted ; ten- 

 tacle long, white, with blackish line. 



Shell about three eighths of an inch long, and two 

 broad, convex above and flat underneath, obscurely 

 striate transversely, of a greenish or whitish colour, 

 variously chequered with spots or bands of white, 

 brown, purple, or pink; spire consisting of three 

 volutions, the first very large, oblong, and oblique, 

 the others small and lateral; aperture horizontal, 

 semielliptic, with the margin sharp and entire ; pillar 

 white, transverse, sloping down to a sharp edge, and 

 quite entire ; operculum semilunar, yellowish, with 

 an orange border, and underneath is a strong raised 

 grooved spire at one end. 



The shells are often covered with calcareous in- 

 crustations, deposited by the water, which make 

 them look like pieces of dirt, and thus escape being 

 seized on by the fish. 



The continental conchologists have described se- 



