80 LITTORINID^.. 



It ranges to the coasts of Sweden (Loven), and is found 

 fossil in the coralline crag of Sutton (Searles Wood). 



There is not the slightest ground for regarding this 

 species as the type of a genus distinct from Bissoa. 



R. CRENULATA, ISIichaud. 



Oval-acute, solid, coarsely caucellated by longitudinal and 

 spiral costella), of which latter there are not more than three 

 rows on the penult whorl ; throat crenated. 



Plate LXXIX. fig. 1, 2. 



Turho canoellntus. Da Costa, Brit. Conch, p. 104, pi. 8, f. 6, 9. 

 „ cimex, (not Linn.) Donovan, Brit. Shells, vol. i. pi. 2, f. 1. — Moxt. Test. 

 Brit. vol. ii. p. 315. — Maton and Rack. Trans. Linn. Soc. 

 vol. viii. p. 161. — Rack. Dorset Catalog, p. 49, pi. 14, f. 6, 9. — 

 TuRT. Conch. Diction, p. 210. — Dillw. Recent Shells, vol. ii. 

 p. 821.— Wood, Index Testaceolog. pi. 30, f. 15. 

 Cinguht „ Fleming, British Animals, p. 305. — Brit. Marine Conch, p. 174. 

 Rissoa crenidata, Michaud, Nouv. Especes de Riss. p. 15, f. 1, 2. — Potiez and 

 Mich. Gal. Donai, Moll. vol. i. p. 269. — Desk. Lam. Anim. 

 s. Vert. (ed. Desh.) vol. viii. p. 465. — Philippi, Moll. Sicil. 

 vol. ii. p. 126. 

 „ cimex. Brown. Illust. Conch. G. B. p. 1 1, pi. 8, f. 21, 22, 



As the name given by Da Costa, in one of his many 

 ungenerous attempts to deprive Linnceus of the honour of 

 nomenclature, was bestowed by him on a shell which he 

 erroneously believed had already received a prior appella- 

 tion, it cannot take precedence of the subsequent one by 

 Michaud. 



This well known Bissoa, perhaps one of the most dif- 

 fused species of its genus, has an ovate acute figure, is 

 strong, yet a little translucent, and is of an uniform 

 yellowish white, or merely with a subsutural zone of 

 fulvous, and another near the basal extremity of the shell. 

 The exterior is coarsely cancellated throughout by equal- 



