178 INSECT TRANSFORMATIONS. 



days.' The fact is, that few spiders live one year, 

 much less three; and all their changes of skin are 

 gone through in a few months, and their acquiring 

 new legs for mutilated ones takes some weeks. It is 

 probable, indeed, that Goldsmith never thought of as- 

 certaining the identity of this spider; if the whole story 

 be not a mere fancy, like his assertion that spiders, 

 ' when they walk upon such bodies as are perfectly 

 smooth, as looking-glass or polished marble, squeeze a 

 little sponge which grows near the extremity of their 

 claws, and thus diffusing a glutinous substance, adhere 

 to the surface till they make .a second step.'* Nei- 

 ther spiders nor any insects with which we are ac- 

 quainted can thus produce gum from their feet to aid 

 them in walking upon glass, though the house-fly can 



Goat moth caterpillar (Cossus ligniperda) escaping from a 

 drinking glass, by spinning a ladder of silken ropes. 



* Animated Nature, pt vi, ch. iii. See also Insect Archi 

 tecture, pp. 367-8. 



