The Land Slugs 



it is white, yellow, brown or black, according to the food plants 

 and the moss and leaves among which its life is spent. 



The Arions are late in going into hibernation, sustaining a 

 much greater degree of cold than the shell-bearers. The eggs 

 are laid at intervals covering several weeks, an individual pro- 

 ducing several hundred. They hatch in forty to sixty days. 

 The young slug buries itself in the ground for four or five days, 

 and emerges nearly twice its original size . The adult slug, after 

 laying its eggs, frequently dies from sheer exhaustion. The weight 

 of the eggs laid often exceeds three-fourth of the slug's own weight. 



In every batch of slug's eggs many are devoured by the 

 larvae of a small fly which lays its eggs inside after puncturing 

 the thin shell. Centipedes, ants and other insects devour the 

 young. So do other slugs, and birds have a great liking for them. 



A favourite pastime with A. ater is to take a bath. It often 

 remains under water for hours. One specimen, submerged and 

 held under for three days, did not perish, but recovered in short 

 order. Small parasites make life miserable for many a healthy 

 slug. They may be seen swimming in a beaker into which a 

 slug is put for a bath. Perhaps bathing is the practical means 

 of getting rid of these pests. 



A slug will often eat the slime and even the skin off the back 

 of another. Though this is certain death to the victim, he stands 

 still, making no objection, and seeming quite indifferent to the 

 business which gives his companion so much pleasure. 



Genus ARIOLIMAX, Morch. 



Mantle with free edges all around, and contains a stiff plate 

 of limy composition; body slug-like, blunt. 



The Great Yellow Slug (^A. Columhianus, Gld.) frequents 

 damp, shady places throughout the year on the Pacific 

 coast, and spends the rainy months in the fields. It is -attracted 

 by such a bait as a bit of orange peel or a dish of milk. The many- 

 toothed radula and cross-ribbed jaw are fitted for a vegetable 

 diet. Length, 4 to 6 inches. California northward. 



"The Black Slug {A. niger, Cpr.) is dark, as a rule, with a 

 narrow, long body, blunt in front, two inches long when crawling, 

 an inch long or less when drawn up under shelter to rest. 



Habitat. — Central California. 



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