CARYCH1UM. 73 



This smallest of British shells may be readily distin- 

 guished by its pretty little white or cream coloured, 

 tapering, cylindrical, and spiral shell, which is a line 

 in length and half a line in breadth. Whorls five or 

 six in number, moderately rounded, end tapering to a 

 blunt apex ; peristome broadly reflected. The aper- 

 ture suboval, provided with three or four teeth, one on 

 the outer lip, two on the inner, and one on the pillar 

 lip. 



var. SUBEDENTTJLUM, with the teeth almost obsolete. 

 Animal creamy white with large eyes. 



Hob. Generally diffused over the British Isles. It 

 may be found by carefully looking amongst moss, 

 grass, &c., in damp situations. 



CYCLOSTOMID^E. 



CYCLOSTOMA. Montfort. 



Shell Ovate, spiral, turreted, mouth simple, oval ; with an 

 operculum consisting of four or five oval depressed 

 whorls, terminating in an ecccentric nucleus. 



Animal With a proboscidiform muzzle ; two subulate tenta- 

 cles, with eyes at their external bases. 



C. ELEGANS. Mutter. PI. VII, fig. 48. 



This is the only British representative of this inter- 

 esting genus of mollusks. It may be readily distin- 

 guished by its thick strong shell, which is covered by 

 a purplish brown periostraca which is marked with 

 numerous, close-set, raised, longitudinal striae. Whorls 

 five, simply rounded ; sutures profound and rather 

 oblique ; spire turreted, and terminating in a blunt 

 apex, much sculptured; mouth circular, inside of a 

 reddish colour. The shell is dextral ; length half an 

 inch, breadth one third of an inch. 



The variety marmorea of Brown, is much smaller 

 and more finely striated. 



Animal of a dark brown colour, with an elongated 

 head and subulated tentacles. 



