o 



38 



difcovered, till the aperture has been well cleaned, and 

 it is pofTible even that penetrating naturaiil^ may have 

 overlooked this circumilaiice, in a bad fpecimen of lb 

 minuie a fpecies. 



60. 

 Tridens. Turbo tridens. Gmel. Syjl. p. 3611. — Turi. Lin. iv. p. 499. 



Tab. 11. f. 2. Pult. Cat. Dorfet. p. Ad.— Gualt. t. 4. F. 



Helix tridens. Muller. Vmn. li. p. 106. No. 305. 



T. with a fub-cylindric, fmooth, glofly fliell, of a 

 light-brown colour: volutions fix or leven, fcarcely 

 raifed, or diftinguiflied, but by the feparating line: apex 

 obtule : aperture fmall and curved; outer lip turnifhed 

 with one tooth on the margin ; pillar lip a little rcflexed, 

 with two long and two fhort teeth alternate. Length 

 a quarter of an inch. 



The fpecies here defcribed we received from Doflor 

 PuLTENEY, who has given it in his Catalogue of Z)o7- 

 feljldre fhells ; and who fays it is found on water plants, 

 by the river Stour in DorfdtJJiire. Dead (hells are ufu- 

 ally white. It is pollible mod of this fpecies may have 

 only three teeth, efpecially fuch as are not full grown; 

 thofe we examined were rather larger than ufually de- 

 fcribed, and had all five teeth ; two however are very 

 fmall, and might eafily be overlooked. 



On the authoritv above ftated, it is here given as 



Britijh^ 



