Class VI. HELIX. SNJIL. • ■ 3-^1 



** Wreaths rounded and umbilicated. 



Lin. Sj/si. 1243. No. 671. Faun. Suec. 2179- 6. cornea. 



Gm. Lin. 3623. Lin. Tr. viii. I90. ^'°'""^- 



List. Angl. tab. ii. Jig. 26. ilfow^ Tesf. Br. 448. 

 Gualtieri, tab. iv. D. D. 



He. with four rounded spires ; umbilicated ; 

 of a horny appearance. 



Found in dull deep rivers, and in ponds. 

 The largest of the British depressed species. 

 Tab. Ixxxvi.^^. 3. and j%. *3. *3. a young 

 shell. 



Gm. Lin. 3624. 



Mont. Test. Br. Abb. id. 



7. SPIROR. 



Lin. Tr. viii. IQl. 



Sup. t. 25. f. 2. 



BIS. 



* He. with a concave shell, both sides plane, 

 whitish, and five round volutions ; diameter ^ 

 three tenths of an inch; inhabits stagnant 

 waters and rivulets. 



Gm. Lin. 3624. Mont. Test. Br. 457. id- 8. contor- 



Lin. Tr. viii. igi. Sup. 146, t. 25. /. 6. TA. 



* He. with a subumbilicated shell, plane, equal 

 on both sides, with pointed linear aperture; 

 size of a cabbage seed ; inhabits rivulets and 

 ditches. 



VOL. IV. J 



