175 



Helix nitida. Mutter, Verm. ; Alder, Mag. ZooL $ 



Bot. ii. 107. 



Helix tenuis. Dillicyn. 

 Inhab. moist ditches and marshy places. 

 Animal black or blackish grey; foot and lower 

 side of body grey ; tentacles and neck black. (Sturm, 

 t. 11.) 



The shell appears dark chocolate when the animal 

 is alive, and is about a quarter of an inch 

 in diameter. It differs from Z. ccttaria, 

 Z. alliaria, and nitidula, in being more 

 convex, more regularly striated, of a darker 

 colour, and without any trace of opacity on the un- 

 der side. 



Nilson describes the eggs as depressed, globose, 

 covered with a white calcareous shell. They are 

 solitary, and deposited in May or June. This snail is 

 sometimes so abundant in pine-beds and orchidaea- 

 houses as to be a great detriment to the plant ; hence 

 they have been called Pine Snails and Orchideous Snails. 



54.11. ZONITES excavatus. Excavated Snail, (t.4. 



f. 39.) Shell sub-globular, depressed, shining, 



transparent horn-colour, regularly striated; 



whorls 5 or 6, rather rounded and closely set ; 



base much rounded, umbilicus very large and 



deep, exposing all the whorls to the tip ; aperture 



nearly orbicular lunate. 

 Helix excavata. Bean, MSS.; Alder, Cat. 13. n. 52.; 



Mag. Zool. $ Bot. ii. 107. 

 Helix lucida var. Turton, Man. ed. 1. 57. t. 4. 



f. 39. 

 Helix nitida a. Jeffreys, Linn. Trans, xiii. 339 



511. 



I 4 



