HELIX. 173 



moisture ; but some delight to bask in the sun's rays, 

 and protect their soft and tender bodies from the heat 

 by forming an epiphragm or film that covers the mouth 

 of the shell. They would soon perish if the secretion 

 of slime were checked. Their habits are nocturnal or 

 crepuscular ; and they are seldom met with crawling 

 about in the daytime, unless in wet weather or after a 

 heavy shower of rain. Before the sun has fully risen 

 they retire to their lurking-places and hasten to conceal 

 themselves under stones or logs of wood, among dead 

 leaves, at the roots of grass, in the bark of trees, or in 

 the chinks and crevices of rocks and walls. Some of 

 them, which have no such place of shelter to resort to, 

 attach themselves to the stalks of grass or leaves of trees 

 and other herbage, by means of a secretion like that of 

 which the epiphragm is formed. During the pairing- 

 season they are furnished with crystalline darts which 

 they shoot at each other, after preliminary coquettings, 

 increasing this mutual excitement by long-continued 

 caresses with their horns. These curious love- weapons 

 have been observed sticking in the bodies of snails after 

 such conflicts. They are contained in a special pouch 

 or receptacle ready for use, and are peculiar to the pre- 

 sent genus. Their shape varies according to the species. 

 In some species each individual has only one of these 

 missiles, in others two; and a few species have none 

 at all. The eggs of the Helices, which are usually round 

 and united in a cluster, are laid underground in short 

 and slanting galleries which the mother snail excavates 

 in the moist or loose earth with her foot. The tentacles 

 of these, as well as of all other land-snails, are with- 

 drawn in the same manner as the fingers of a glove 

 turned inside out. 



The present genus, as restricted by some conchologists, 



