112 DRAGONFLIES OF OHIO. 



Female colored like the male, except her front is 

 lighter, usually yellowish. Vulvar lamina short, most 

 prominent at the sides. 



The large size of this species separates it from 

 other Ohio members of the genus. 



One should observe corrupta in the field for one 

 season to become thoroughly acquainted with its 

 variations. If he does not know it in all its stages 

 to begin with, and if he is eager to obtain the greatest 

 number of forms possible in a certain locality, he can 

 easily convince himself that the various colorations 

 it presents, represents at least three distinct species. 



It is common in all parts of the state during July 

 and August. 



PERITHEMIS, Hagen. 



In the single species of this genus, the hind wings 

 are longer than the abdomen. Although very 

 common around water, it is not conspicuous because 

 of small size and rather secluded habits. It flies low 

 and rests a part of the time on water plants or any- 

 thing that projects above the water. While its 

 colors are developing after emergence it may be 

 found in the fields some distance from water. Males 

 and females are taken usually in about equal members. 



Perithemis domitia, Drury. 



Length: of abdomen d 14-15, ? 13-14; hind wing 9 

 19-20, 9 19-20. 



Male, colors yellowish to brown, wings uniform 

 yellowish or sometimes with a brownish point above 

 the triangle. Thorax often with two olive, lateral 

 bands o r with each band represented by a small spot 

 below the middle ; these thoracic markings may be 

 obscure or wanting. Abdomen nearly uniform 

 brown in dry specimens. 



Female, front wings with costal margin yellowish 

 nearly to pterostigma, a patch at nodus extends 



