68 



MOLLUSC A. 



VALUE. Cultivated for food an important industry in France. 



NOTE. Most of the snails hibernate in the cold seasons, and will 

 live for years without food. The largest are the agate shells of 

 Africa, eight inches across ; the eggs an inch in length, with a 

 hard covering. The Helicarion gutta of the Philippine Islands, ac- 

 cording to Semper, when caught by the tail, throws it off and so 

 escapes, the tail in time growing again. This is also the case with 

 a West Indian snail (Stenopus). Helix hortensis, common in New 

 England, was introduced years ago from England. Helix fidelis is 

 an albino, found in Washington Territory. 



FIG. 71. Bulimus rosaceus. 



Land-Slugs (Limcidce). These slugs (Fig. 70, C), of 

 which 1 16 different species are known, are common in every 

 garden, and their bright- 

 yellow eggs found under 

 old boards or buried in the 

 ground. They have, as a rule, 

 a rudimentary scale-like shell 

 (Fig. 70, S), long tentacles, 

 and are carnivorous, eating 

 worms and other animals. 

 They have a curious secre- 

 tion by which they lower 

 themselves from twigs and 

 leaves. It is also a defense, 

 and when applied to many 

 animals, as moles, is often 



' \ FlG. T2.Onchtdtum tonganum, a 



fatal. Umax UOCtlluca, from m ollusk with dorsal eyes ; natural 



Teneriffe, has a luminous size. 



