340 HALF HOURS WITH INSECTS. [Packard. 



tures are in a sense free agents, and are able to make a 

 slight use of physical laws through the exercise of reason. 

 It is probable that after thousands of generations these 

 habits, at first slowly and painfully acquired, have become 

 moulded into instincts, sometimes even nowadaj-s at fault. 

 For wasps and bees may make mistakes as well as men. 

 My assertions would assume the form of arguments could I 

 lay before the reader the multitudes of shapes in which 

 wasps and bees build their nests. The gradations from the 

 simple nests of the solitary wasps up to the complicated, 

 enormous nests of some species of Vespa are manifold, and 

 are evidences that their different styles of architecture are 

 outgrowths of a single, simple spherical cell, each kind dif- 

 fering according to the intellectual traits of its builder and 

 the peculiar exigencies of its life. 



The cells of these wasps, though for the most part con- 

 structed of bits of wood and the bark of trees gnawed off 

 by the wasp, are in their earliest stages largely composed of 

 silk secreted in the salivary glands of the wasp. Perhaps 

 chewing this woody matter promotes a freer flow of the se- 

 cretion. At any rate the silk is plastered on thickly bj^ the 

 wasp. She is very careful to have the common pedicel, by 

 which the cells are suspended, of great strength ; it must 

 therefore consist almost entirely of silk. I have watched a 

 Polistes by the hour, plastering the pedicel with silk, going 

 over it with its tongue, and proving its work with its sensi- 

 tive antennae, which rapidly patted the work as if they were 

 fingers. 



By the time three cells are perhaps one-half made, the 

 wasp lays an egg at the bottom of two of them ; by the time 

 the fifth cell is partly completed, the four others each con- 

 tain an egg. As the cells increase in number through the 

 industry of the parent, more eggs are laid. The young 

 hatch from the eggs first laid, and now the duties of the 

 parent wasp are doubled. She feeds the young with flies 



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