22 LITTORINID^. 



of the eyes at the tip of the tentacle, as in Helix and 

 its allies, and not at the base. It would appear as 

 if there were in reality no tentacula, and only the 

 tubercle, common to many Mollusca, at the base of 

 the tentacula, a little more developed than usual." 

 I am inclined to retain my former theory; for if the 

 pedicle of the eye of this genus is minutely examined, 

 it will appear to be formed of two parts united by a 

 suture. 



There has been a great controversy about this 

 genus. Consult Ann. and Mag. Nat. Hist. 1855, 

 xvi. pp. 114. 184. 272. and 422. ; 1836, xvii. 49. 56. 

 A shell which I described from India, under the 

 name of Turho Francesia (Wood, Supp. t. 6. f. 28.), 

 has been found by Mr. Benson to have the same kind 

 of animal, and to be a second species of the genus. 

 The central tooth is wider beloAV, the base trun- 

 F;g_ 2. cated in the middle, 



prominent on both 

 sides ; produced into 

 a horn, cutting edge 

 triangular, with five 

 or seven pointed 

 lobes. The first la- 

 teral tooth with seven lobes, the third lobe larger ; 

 the second slender, upper part claw-like, serrated 

 on the outside ; the third tooth rounded at the tip, 

 ciliate, denticulate (fig. 2.). 



2. 1. AssiMiNiA Craya/za. Liver-coloured Assiminia. 

 — Shell ovate, acute, solid, liver-brown ; suture 

 slightly impressed ; mouth ovate, (f. 127.) 



