HYMENOPTERA. 



This is the order of the sawflies, the gallflies, the 

 ichneumon flies, the horntails, the wasps, the bees, and 

 the ants. 



Among the members of this order are to be found 

 the wonderful examples of community life which are not 

 equaled elsewhere in the animal kingdom. And yet, 

 while the community life of the social bees, ants, and wasps 

 is certainly matter for wonder, the life of the solitary 

 wasps and bees is not less wonderful in its wealth of 

 economy, scheme, and device. 



The order furnishes also the most interesting exam- 

 ples of parasitism in the animal kingdom. According to 

 Fiske, the American tent caterpillar is liable to be para- 

 sitized by no fewer than twelve species of Hymenoptera. 

 Six of these primary parasites may be parasitized by 

 secondary parasites, also hymenopters. Four of the 

 secondary parasites are in turn parasitized by tertiary 

 parasites ; and one of these tertiary parasites may be 

 parasitized by an hymenopterous parasite of the fourth 

 rank. Not much chance for the tent caterpillar in the 

 midst of all this! 



" Big fleas have little fleas 

 Upon their backs to bite 'em; 

 And these in turn have lesser fleas, 

 And so on, ad infinitum." 



All members of the order have four clear, membranous 

 wings destitute of scales. The front wings are larger than 

 the hind wings and bear the brunt of the flight activities ; 



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