thirteen] securing OUR ALLIES 



early autumn a generation of males and females is 

 produced. A good observer says, "I would rather 

 have a colony of hornets in my orchard when it is 

 infested with slugs, than to have the same number 

 of barrels of London purple sprayed on my trees." 

 They work hard all day, picking lice or slugs from 

 the trees, which they devour or carry to their 

 young. 



If all bees visited, indiscriminately, every sort of 

 flower, it would happen that the pollen from one 

 species would be carried to a wholly different 

 species, where it would be useless. It is desirable 

 that each kind of bee visit one particular kind of 

 plant, or at least a few kinds. This proves to be 

 the case, for there are many bees that never visit 

 more than one sort of flowers. As the number of 

 species of flowers is very great, it is not surprising 

 that there are many kinds of bees. In many in- 

 stances the mouth part of the bee is nicely suited to 

 the flowers they select. Certain kinds, with very 

 long tongues, suck nectar from long, tubular flow- 

 ers, such as the yellow-flowered currant, while 

 others, with short tongues, make use of shallow 

 flowers. There are already reported nearly two 

 thousand different species of wild bees in North 



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