126 UNIVALVES. — HELIX. 



in many parts of Europe as an article of food during Lent, 

 and was considered a luxury by the Romans. It is ovi- 

 parous, and very tenacious of life; towards winter, it co- 

 vers its aperture with a calcareous lid, resembling an oper- 

 culum, and remains in a torpid state until the spring. 

 The animal of the H. ampullacea in the sixth division 

 grows to an immense size, and is also eaten; its eggs, 

 which it deposits in clusters on the bark of trees, or rushes, 

 &c. have sometimes a pink tinge, but are generally dull 

 white. 



Of the species which compose the fourth division, may 

 be adduced the H. dextra and the H. perversa (a syn- 

 onym), which differ only in the direction of their whirls : 

 they are both rare shells, and have their surfaces covered 

 with a beautiful citron colour, variegated with green, and 

 striped or banded with brown. The H. ovata and H. ob- 

 longa are both land shells ; the eggs of the animals are per- 

 fectly elliptical, and nearly equal in size to those of the com- 

 mon sparrow. The animals of the H. ianthina and H. glo- 

 bosa, forming the eighth division, have the property of emit- 

 ting a phosphorescent light, and stain the hand of a pur- 

 ple colour, not easily removed; they are found in great 

 numbers, floating on marine substances. 



Amidst the endless variety of terrestrial shells, there is, 

 perhaps, no species so well known as the H. nemoralis or 

 common garden snail; it is an inhabitant of European 

 gardens and orchards, and very destructive to fruit and 

 tender leaves. Its eggs are perfectly round, and about the 

 size of small peas. 



A very beautiful and rare species of the third division is the 

 H, hsemastoma, which is admired for its elegant bandings 

 and rose coloured lips. A black lipped variety of this shell 

 has lately been discovered, which is also rather rare ; the 

 body of the shell being pink, forms a beautiful contrast 

 with its jet lips. 



