CHAPTER XXVII 

 ORDER HYMENOPTERA* 



Bees, Wasps, Ants, and others 



The winged members of this order have four wings; these are membranous 

 and have the wing-venation more or less reduced. The hind wings are smaller 

 than the fore wings. The mouth-parts are formed for chmving or for both 

 chewing and sucking. The abdomen in the females is usually furnished with 

 a sting, piercer, or saw. The metamorphosis is complete. 



The Hymenoptera is a very large order, including a vast number of 

 species. The bees, wasps, and ants are among the better-known members 

 of it ; but in addition to these it includes a large number of less familiar 

 forms. Many of these are minute parasites of other insects; others 

 cause the growth of galls on plants; and still others, in their larval state, 

 feed on the foliage of plants or are borers in the stems of bushy or her- 

 baceous plants or in the limbs and trunks of trees. 



The members of this order are chiefly of small or moderate size, and 

 many of them abound wherever flowers bloom. From very early times 

 some of them have been favorites with students of the habits of animals, 

 for among them we find wonderful developments of instinctive powers. 

 Many volumes have been written regarding their ways, and much re- 

 mains to be discovered, even concerning our most common species. 



The membranous nature of the wings, which suggested the name of 

 the order, is not a distinctive characteristic, for it is possessed by the 

 wings of many other insects. 



The two pairs of wings are similar in texture. The wings of each side 

 are held together by a row of hooks, the hamuli, on the front margin of 



Fig. 571. — Wings of bee showins hamuli, h. 



the hind wing (Fig. 571) ; these hooks fasten to a fold in the hind margin 

 of the front wing, so that the two wings present a continuous surface. 

 The hind wings are smaller than the fore wings and have a more reduced 

 venation. Some forms are apterous. 



* Hymenoptera: Hymen (iW), membrane; pteron {irrepov), wing. 



329 



