40 COLIMACEA. 



each other as they recede inwardly ; lips thick, while, and con- 

 tinuous and detached all round. 



This species is distinguished from C. hidcns by its colour, 

 superior size, and particularly in the shape of the aperture, the 

 margins of which are reflexed and produced, and the teeth are 

 much closer together in proportion to the size of the shell. 



First identified as a British species by Colonel Montagu, who 

 discovered it at Easton Grey, Wiltshire, and has been found in 

 Hyde Park, London. Its chief habitation is in woods and 

 close-set hedges. 



3. Clausilia rugosa, pi. IV, f. 37j 38. 

 Clausilia rugosa, Drapernaud, Hist, des Moll., p. 73, pi. 4, 

 f. 19, 20; Pfeiffer, p. 63, pi. 3, f. 30; Leach, Moll., p. 121 ; 

 Turton, Man., p. 74, f. 58 ; Alder, Mag. Zool. and Bot., II, p. 

 Ill; Clausilia perversa, Fleming, Brit. An., p. 271; Clausilia 

 nigricans, Jeffreys, Linn. Tr., XVI, p. 351; Thompson, Ann. 

 and Mag. Nat. Hist., VI, p. 42 ; Clatisilia parvula, Leach, 

 MSS. ; Turton, Zool. Journ., II, p. 556 ; lb., Man., p. 74, f. 

 58 ; Jeffreys, Linn. Tr., XVI, p. 352 ; Turbo nigricans, Dill- 

 wyn, Cat., p. 375 ; Turbo perversus. Pennant, Brit. Zool., IV, 

 p. 130, pi. 82, f. 116; Turbo bidens, Montagu, Test. Brit., p. 

 357, pi. II, f. 7; Brown, Ency. Brit., 6th Ed., VI, p. 556; 

 Helix perversa, Muller, Verm., p. 118; Brown, Wernerian 

 Mem., II, p. 523 ; Clausilia rugosa, Brown, lUust. Conch., p. 

 38, f. 14 ; lb.. First Ed., pi. 41, f. 14. 



Variety 1 . Shell smaller, and more slender inform. 

 Variety 2. Shell shorter, toith fewer volutions. 

 Clausilia Everetti, Ann. Phil., N. series, XIX, p. 377. 

 Shell somewhat opaque, blackish or chocolate-brown, fre- 

 quently with ash-coloured or whitish longitudinal streaks, 

 slender ; with about twelve volutions, slightly inflated in the 

 middle, and covered with elevated, granular, longitudinal strise ; 

 aperture oval, the inner lip a little contracted, the columella 

 provided with three plaits, the lower one placed interiorly, 

 and scarcely discernible in the adult shell ; lips thick, detached 

 from the body, and pure white. Length generally about half 

 an inch. 



This is the most common species of Clatisilia; inhabiting 

 rocky or woody situations; it is subject to great variety in size, 

 and even diameter. It is generally distributed throughout 



