CLAUSILIA. 121 



and subcolumellar fold, for the most part, tolerably evi- 

 dent ; a single posterior (subsutural) palatal ridge. Ordi- 

 nary size three-fifths by a full eighth of an inch ; but 

 sometimes larger. 



The animal is very short, thick, and broad, rugosely 

 granulated, of a dead dusky blackish grey, the dark colour 

 broken up into lines and squarish spots as it approaches 

 the paler margin of the foot. Sole of the foot greyish- 

 white, tail broad, linguiform. Upper tentacles stout and 

 clavate, black ; lower ones extremely short, paler. When 

 at rest and protruded, it carries its upper tentacles nearly 

 erect. This description is drawn up from some living 

 examples communicated by our talented friend Mr. W. 

 Thomson, of King's College. 



This rare species was first discovered in Britain by Mr. 

 Rolph, who found it in Charlton Wood, Kent. It occurs 

 in other Kentish localities. Hastings, Sussex (Gray) ; 

 Hampshire ; Dovedale in the Marsh, Gloucestershire 

 (Beevor, Jeffreys). 



C. nigricans, Maton and Rackett. 



Slender, chocolate brown : the raised striae crowded, fine, sub- 

 granular ; mouth small, with three plaits. 



Plate CXXIX. fig. 1, 2. 



Strombiformis perversa, young, Da Costa, Brit. Conch, p. 187.* 

 Turbo perversus, Pulteney, Hutchins, Hist. Dorset, p. 46, in part. — Donov. 

 Brit. Shells, vol. ii. p. 72. 

 „ Helens, (not Linn.) Mont. Test. Brit. p. 357, pi. 11, f. 7. 



* The shell which Da Costa describes as the adult state of this species appears 

 distinct, and if indigenous, was probably one of our larger corrugated species. He 

 states that it differs from the young in being double or treble the size, with coarser 

 stria3, and proportionally stronger in its several parts : he further states, that most 

 have eleven or twelve turns, and some are bidentated, and that the much reflected 



VOL. IV. R 



