324 AN INTRODUCTION TO ENTOMOLOGY 



Family AGRIONID^ 

 The True Agrionids 



In the Agrionidae the wings are furnished with many antenodal 

 cross-veins; and, although the wings are narrow at the base, they 

 are not so distinctly petiolate as in the next family. These insects 

 may be termed the true agrionids, as owing to a misapplication of the 

 generic name Agrion the members of the next family have been 

 incorrectly known as the agrionids. 



Here belong the most beautiful of our damsel-flies, whose metallic 

 blue or green colors are sure to attract attention. They are feeble in 

 flight and do not go far from the banks of the pond or stream in 

 which they were developed. 



There are only two genera of this family in our fauna. These are 

 Agrion, which has been commonly known as Calopteryx, and Hetce- 

 rtna. In Agrion the wings are broad and spoon-shaped. In Hetce- 

 rlna the wings are rather narrow, and in the males the base of one or 

 both pairs is red. 



Family CCENAOillONID^ 

 The Stalked-winged Damsel-Flies 



The members of this famiily are easily recognized by the shape 

 of their wings, which are long, narrow, and very distinctly petiolate 

 (Fig. 368); and by the fact that in each wing there are only two 

 antenodal cross-veins, except in a few cases where there are three or 

 four. 



To this family belong the smallest of our damsel-fiies ; but while 

 our species are of small or moderate size, there exist in the tropics 

 species that are the largest of the Odonata. Some of our species are 

 dull in color; but many are brilliant, being colored with green, blue, 

 or 3xllow. This family includes the greater number of our damsel-flies. 



