99 



Helix rotund ata (The Radiated Snail). MiiHer. 

 Figures 71 and 72. 



71. 72. 



Probably better known in ihis couulr}' as th-e Zonites 

 rotundatus of Gray and Macgillivry. 



It was described as early as the year 1678, by Dr. 

 Lister, under the name of Zonites radiatus. ^ 



A somewhat flat shell, being nearly similarly convex 

 on either side; thin, but not fragile; deep strice, semi- 

 transparent, aperture small and lunate, umbilicus large 

 aad profound. There are from five to six and a half 

 convolutions. Spire convex. The colour of the shell 

 is reddish-grey, with streaks of a chesnui hue running 

 from the centre. 



Usual diameter a quarter of an inch. 



The colour of the animal is blueish. 



Common throughout Great Britain and Ireland, 

 under stones and decayed wood, and occasionally in 

 damp outhouses. The largest specimens from this 

 neighbourhood were procured from the scullery at 

 Highfield House, located in crevices between the wall 

 and the stone floor. 



There are two marked varieties: — The first with the 

 spire quite flat, known as Helix Turtonii. The second 

 colourless, or nearly so, transparent, and devoid of rays. 

 The latter variety is rare. 



M. Bouchard Chautereaux remarks that they deposit 

 from twenty to thirty eggs at a time, which are from 

 thirteen to twenty days in hatching, becoming fully 

 grown in a year. This ^reat conchologist is in error 

 with respect to the period at which they commence lay- 

 ing eggs, for on the 12th of March of the present year 



