INSECTS. 115 



skillfully build it into serviceable houses. The mud 

 wasp is a mason who knows his trade well, andean 

 build a more beautiful and complex house than 

 any beaver or bird with the same material. 



If any insects can be called domestic, bees and 

 silk moths are truly such. Honey of bees is not 

 only pleasant to the taste but it also has a high 

 food value. It is a common article of diet at all 

 times of the year, and its commercial value is of 

 no small importance. The caterpillar of the silk 

 moth spins material that is worn in some form or 

 other by nearly all of the human race. Silk is not 

 only used for clothing but is woven into fabrics for 

 almost numberless purposes. The silk worm does 

 not thrive well in the United States, yet the silk 

 trade is very extensive. The combined silk indus- 

 tries of the 4 world amount to hundreds of millions 

 of dollars. It seems almost impossible that so 

 small an insect could be of such service to human 

 beings. 



INSECTICIDES. 



Different substances are used to kill insect pests 

 of the farm and garden, but certain underlying 

 general principles should govern the intelligent use 

 of all of them. Chickens, as well as other birds, 

 both wild and domestic, like to wallow in dust. 

 They do it to kill the bird lice on them. Insects 

 breathe by means of small tubes arranged along 

 the sides of the body. These tubes, or breathing 



