Since that period we have taken it in a ditch, or water- 

 courfe iubjecl to be overflown by the river Au7i, near 

 Hatch, in Devonjhirc; and in the Avon, at Lackham, in 

 WiltJJdre, iparingly; and lately in great abundance in a 

 fmall pond under the downs, clofe to the village of Wed- 

 hampton, in the lad county; where neither the corneum 

 nor avinicum were to be found. It is remarkable this 

 pond, which affords one or two other of the more rare 

 fhells, efpecially the Helix nmttiloides, has no communi- 

 cation with any other water, but Hands expoP^^d at a very 

 confiderable diftance from any, and much higher than 

 any in the neighbourhood. 



It is fcarcely poffible this ffiell cap be confounded with 

 the C. corneum, if the fmalleft attention is paid to the re- 

 markable produced umbo, and the comprefTed fpreading 

 margin, independent of the fub-rhomboidal Ihape, moft 

 conrpicuous in full grown fpecimens. 



There is no doubt this is the Tellina lacujiris of Mul- 

 I.ER, though he fays it has fix lateral teeth, and no mid- 

 dle ones. Chemnitz obferves that a good magnifying 

 giafs is required to find all the teeth Muller has given 

 it, but that it has middle teeth, though they are very fmall. 



In the larger, or full grown fl.ells, there is no difficulty 

 in difcovering by thealfiUance of a good pocket lens, or 

 hand meg;alafcope, the fix teeth delcribed by Muller, as 

 well as the central ones : but younger (hells are fo ex- 

 tremely 



