CHAPTER XV 



THE SAW - FLIES, GALL - FLIES, 

 ICHNEUMONS, WASPS, BEES, 

 AND ANTS (Order Hymenoptera) 



EES, ants, and wasps are the familiar Hymenoptera. 

 They are the "intelligent" and the "social" in- 

 sects, and therefore seem, of all the insect hosts, 

 those living the most specialized or "highest" kind 

 of life. As intelligence and social life are precisely 

 those characteristics of our own which most dis- 

 tinctly set us off from other animals, we are quick 

 to appreciate the worth of similar attributes in the 

 "ant and bee people." But in actual degree of 

 specialization of instinct 

 and behavior the perform- 

 ances of the solitary wasps 



and bees are little less wonderful than those of 

 the social kinds, and the amazing character of the 

 life-history of many of the obscure and unfamiliar 

 parasitic and gall-making Hymenoptera ought to 

 incite as much interest and scientific curiosity as the 

 marvels of the bee community. The Hymenoptera 

 constitute a large order, 7500 species in this coun- 

 try, and one of endless variety of habit and struc- 

 ture. Few generalizations indeed can be made that 

 will apply to all the members of the order, although 

 there is no question concerning the true relationship 



of all the kinds of insects included in the order. Of Fl , G - 645 --Mouth-parts of a 



honey-bee with maxilla 



the structural characteristics common to the Hymen- and mandible of right side 



md., mandible; 



optera the clear, membranous condition of the two 

 pairs of wings gives the name to the order (hymen, 

 membrane; pteron, wing). The front wings are 

 larger than the hind ones, and all are provided with 

 comparatively few branched veins, whose homologies 

 have not been fully worked out. The workers 

 (infertile females) of all the ant species are wingless, 



removed. 

 mx., maxilla; mx.p., max- 

 illary palpus; mx.l., max- 

 illary lobe; st., stipes of 

 maxilla; cd., cardo of max- 

 illa; /*'., labium; sm., sub- 

 mentum of labium; m., 

 mentum of labium; pg., 

 paraglossa; gl., glossa; 

 li.p., labial palpus. 

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