Shells of Common Occurrence. 137 



mucilaginous matter, animal and vegetable, slugs, 

 when boiled, have been employed as a cure for 

 consumption. When hard pressed by hunger only 

 will they eat dead earth-worms, and hence their 

 blight falls chiefly on the growing plant. The 

 observer may occasionally have felt startled to see 

 the Limax suspended by an almost invisible but 

 very tenacious thread which it possesses the power 

 of spinning, betwixt him and the light. This is 



1. Limax agrestis (the Milky Slug), Mutter. 2. L. flavus 

 (the Yellow Slug), Linnceus. 3. L. arborum (the Tree 

 Slug), Ghautereaux. 4. L. cinereus (the Spotted Slug), 

 Mutter. 



used by the slug to drop from on high. Like the 

 spider, it exudes this mucous thread from the 

 secretions of its body. Encumbered with no 

 mansion which it must carry on its back like the 

 snail (Helix), the slug is yet more hardy without 

 its shelter than the Helix, and remains active far 

 into the winter, when the other lies dormant in the 

 crevice of the wall. 



The most common slug of the fields, L. agrestis, 

 or milky slug, about an inch and a half long, is the 



