CLOSE-SHELLS. 67 



near the Serpentine. G. rugosa (PL VIII., fig. 11) 

 has been found by Mr. Gwyn Jefi'reys on marshy 

 ground near Battersea ; and C. laminata (PL VIII. , 

 fig. 9), although not so common, is nevertheless 

 reported an inhabitant of trees upon the London 

 clay. The fourth British species, C. rolphil 

 (PL VIII., fig. 10), is very local; but we shall have 

 occasion to notice it at greater length when treating 

 of the shells which inhabit the chalk. 



We have not pointed out the distinguishing 

 characters of the different species of Clausilia, 

 and it is by no means easy to do so in a few 

 words. Some idea of their appearance, size, and 

 colour may be gained by reference to the figures on 

 Plate VIII., but in this, as in other cases, the col- 

 lector will derive the best assistance from an inspec- 

 tion and comparison of well-authenticated specimens 

 in the cabinet of some friend. "We may direct 

 attention, nevertheless, to the variation in the form 

 of the mouth in the different species, and to the 

 number and arrangement of the so-called teeth. 



F 2 



