387 



Helix vivlpai'a. Turt. Lin. iv. p. 528. 



Hill Swanimerd. p. 75. t. 9. f. 13. 



PuU. Cat. Dorfet. p. 48. 

 Helix compaClilis. Id. p. 43. (young.) 

 Cochlea vivipara. Da Cojla. p. 81. t. 6. f. 2. 2. 

 Nerita vivipara. Mailer Verm. ii. p. 182. No. 370. 



H, with fix ventricofe fpires, feparated by a deep, de- 

 prefTed line : fliape fub-conic, fuddenly terminating in 

 a fmall point: colour olive-green, with three brown 

 fafcice on the body, and two on the fnperior volutions, 

 growing fainter, and becoming obliterated before they 

 reach the fourth fpire : it is (lightly wrinkled tranfverfely, 

 with two or three ftronger, and coarfer than the reft, 

 that feem to mark the annual growth of the (hell : aper- 

 ture fub-orbicular, contracted a little at the upper part ; 

 pillar lip reflefted, behind which, in fome, is 2ifub-uvi- 

 bilicus ; infide fmooth, white, banded like the outfide. 

 Length rarely an inch and a half; breadth one inch. 



Da Costa is certainly miftaken, in faying this fliell 

 is found in great abundance in all our rivers and llagnant 

 waters ; for except in the Thames, and other waters 

 communicating with that river, we have never found it. 

 In the neighbourhood o^ Reading, near the junction of 

 the Kennet with the Thames, and in ftreams, and watcr- 

 Gourfes about that place, it is in vafl abundance; but 

 becomes fcarce farther up the former river, and is wholly 

 loft before it reaches Newbury. 



Ddd 2 The 



