KELLICOTT. 91 



drawn from the anal angle to the fourth antecubital. 

 Different specimens vary in this respect, in some the 

 dark marking is slightly reduced while in others it is ex- 

 tended. This characteris constant in Maine specimens, 

 kindly loaned me by C. C. Adams, in New York speci- 

 mens and in Indiana specimens, so that, in none I have 

 seen is there necessity of confusion with cynosura. 



Taken at Columbus and observed at Delaware, in 

 May. 



SEVENTH SUB-FAMILY. 



LIBELLULIN^. 



Twenty-eight species of Ohio dragonflies fall under 

 this sub-family. They are second to the AGRIONIN^B 

 when number of species is considered, but are by far the 

 most conspicuous forms of our odonat fauna in all situ- 

 ations, especially during the summer season. Stagnant 

 pools and ponds, skirted by sedges, cat tails and water 

 lilies are especially attractive to them. Here the males 

 fly back and forth, catching small insects for food, and 

 searching for the females. While pursuing this appar- 

 ent pleasure many of them sacrifice their lives to 

 satisfy the greedy appetite of the king bird who 

 perches himself on a branch of a nearby tree where he 

 can view the proceedings and swoop down whenever he 

 is sure he can procure a dragonfly* for his trouble. 

 Presently at your feet you observe the female with 

 wings almost motionless, waving up and down, and 

 at each downward movement, striking the tip of her 

 abdomen on the surface of the water. She is oviposit- 

 ing. If with a water net a quantity of the debris near 

 the bank be procured a dozen or more nymphs of 

 various stages are usually included. Thus one might 

 seat himself and write out nearly a full life history of a 

 dragonfly from the material of a few minute's 

 collecting. 



