CERITHIUM.— Plate VI. 



The window Cerithium. Shell taperiug, acuminated, 

 white, varicose, whorls longitudinally plaited and 

 cancellated by the crossing of sharp spiral ribs, in- 

 terstices chestnut-colour, aperture rounded, outer lip 

 thick, crenulated within. 



SoWERBY, Thes. Conch. Cerithium sp. -iO. 



Hab. ? 



The peculiarity of this shell consists in the square hol- 

 lows formed between the longitudinal plaits and the raised 

 spiral lines which cross them. 



Species 40. (Mus. Cuming.) 



Cerithicm musichm. Cerith. testa brevi, subventricosd, 

 alba, niffro-lineatd et maculatd, anfractibus pauc'm, 



su-pra medium anyulaiis, inter angulum et siiluram ex- 



cavaiis, ultimo anfraclu magna, ovali, aperturn effiisd. 



caiiali brevissin/.o, obliquo. 

 The music Cerithium. Shell short, rather ventrieose, 

 1 white, with black lines and spots, whorls few, angu- 



lated above the centre, rather hollow between the 

 I angle and the suture, last whorl large, oval, aperture 



effuse, canal very shoi't, oblique. 

 I Sowerby, Thes. Conch. Cerithium sp. 68. 

 Eab. ? 



The proportions of this shell are very differeut from 

 those of C. vulgatiim, the last whorl occupying more than 

 half the length. In characteristic specimens the music- 

 like lines are crossed by lines and spots. 



