HOW TO KNOW THE INSEQS 



Fig. 71. Anax Junius 

 (Drury) 



Thorax green, abdomen 

 bluish. Femora reddish; 

 remainder of legs blackish. 

 Vi/ings transparent with am- 

 ber sheen. Length 76 mm. 

 Expanse 104 mm. 



This family includes our 

 largest and swiftest fly- 

 ing dragon flies. They 

 are often seen long dis- 

 tances from water. L'os- 

 quitos, moths, and many 

 other flying insects make 

 up their diet, which they 

 Figure 71. tear apart and eat with 



their large jaws. In some 

 regions they have proven 

 a pest to bee raisers by destroying large numbers of honey bees. 

 3b Antenodal cross veins in second row a continuation of those 

 in the first row (a). Triangles in fore and hind wing unlike 

 in shape and differently placed. (The Skimmers.) Fig. 72. 



Family 2, LIBELLULIDAE 



Figure 72. 



ent patterns for the two sexes. 



and proportionately heavier than in the Aeschnidae. 



Fig. 72. Libellula lactuosa 

 Burm. The Widow. 



Abdomen blackish, striped 

 with yellow; legs dark. Base 

 of wings marked v/ith brown. A 

 common Iowa species. Length 

 47 mm. Expanse 84 mm.. 



This family of dragon flies 

 is considerably larger than the 

 preceding in number of species. 

 They cover a rather wide range 

 in size and show many brilliant 

 colors with frequently differ- 

 The abdomen is usually shorter 



KEY TO THE FAMILIES OF THE ORDER ORTHOPTERA 



1a Hind legs for leaping. Three or four tarsal segments. . 2 



1b Hind legs not fitted for leaping. Five tarsal seg- 

 ments 5 



2a Three tarsal segments 3 



2b Four tarsal segments. Antennae usually longer than body. 

 (The Long-horned Grasshoppers) Fig. 73 



Family 5, TETTIGONI I DAE 



52 



