HELIX. SNAIL-SHELL. 59 



goes down to the bottom, nor willingly approaches any 

 shore ; for the shell is exceedingly brittle, and that of 

 few freshwater snails is so thin: every shell contains about 

 a tea-spoonful of liquor which is easily discharged upon 

 being touched, and which is of the most beautiful red-pur- 

 ple that can be conceived : it dies linen cloth, and it may 

 perhaps be worth enquiry, as the shell is certainly found 

 in the Mediterranean, whether it be not the Purpuraof the 

 ancients." 



North of Ireland ; Bantry bay ; Le Hinch in the county 

 of Clare ; Portrush ; near Kenmare harbour in the county 

 of Kerry ; Dunmore ; Waterford ; Barnstaple ; the warren 

 between Dawlish and Exmouth ; and Oxwich bay, near 

 Swansea, v. v. 



39. Helix vivipara. Viviparous Snail-shell 



Lister, pi. 1055. f. 6, and Anat. pi. 6. f. 5 Pennant* 

 p\. 87. f. 2, and pi. 88. f. 1, the young Da Costa, pi. 6; 

 f. 2 Donovan, p\. 87 Dorset Cat. pi. 17. f. 2. 



The young, before and after exclusion. Lister, pi. 1054* 

 f. 30. 



Shell thin, transparent, somewhat oval, tapering to a 

 point, slightly striate longitudinally, and generally more 

 strongly wrinkled near the lip : spires five or six, much 

 rounded and separated by a deep line : color olive green, 

 with three dark brown bands on the larger volution, and 

 two on the rest, which grow fainter and become obliterated 

 towards the point : aperture round-oval, contracted a ; little 

 at the upper pat't, reflected at the pillar, with sometimes a 

 small perforation behind it j outer lip thin, projecting and 

 rounded in the middle 5 inside smooth, greenish^white, 

 banded like the outside : length nearly an inch and a half; 

 breadth an inch. . - 



Still waters, and slow rivers, v. v. . . v. 



40. -Helix tremor alls*- Girdled Snail-shell.- ''' 

 Lister', pi. 57. f. 54 Da Costa, pi. 5. f. 1 to 5; ; ahd8, 

 14, 19 Dorset Cut. pi. 21. f: 1 to 5; 8, 14, and 19 Do- 

 Tzowm, pi. 13. 



Shell somewhat globular, semitransparent, glossy, finely 

 wrinkled, with .five rounded volutions, ending rather ob- 

 tusely : color and markings extremely various ; yellow, 



greenish, 



