58 DRAGONFLIES OF OHIO. 



3^ellow, also a spot on basal edge each side of 8 and the 

 whole lateral expansion of 9, the dorsum of 1 and the 

 sides of 1 and 2 are light green. 



The appendages are black, a little longer than 10; 

 the sui^eriors from above are divaricate, base broad, 

 gradually narrowing with the apex obliquely truncated 

 making the inner angle acute ; in profHe they are arched 

 with a tooth at outer angle of the apical truncation, 

 apex slightly turned upward. The inferiors reach the 

 truncation of the superiors, a little more divaricate, 

 apex turned up and obtuse. 



The female differs in having a small black thorn 

 either side of the vertical vesicle, the abdomen a little 

 stouter, the mid-dorsal more distinct, 7, 8, and 9 not 

 quite so much dilated and the spots at base of 8 faint. 

 The appendages are c^'lindrical acuminate, black, longer 

 than 10; the vulvar lamina longer than half of 9, bifid 

 for one third its length, branches acuminate, approx- 

 imated. This is an exceedingly common odonate along 

 the shore of Lake Erie. 



The females fly far out over the waves dipping the 

 abdomen in the water as they fly to wash off the eggs. 

 During June and early in July they may be found on 

 any sunny shore of the lake or bays. They capolate at 

 rest in trees and shrubs. 



Group III. 

 Gotnphus quadricolor, Walsh. 



Length : of abdomen cJ and '^ 32 mm; of hind wing 

 d" 26, ? 27 mm. 



Male black and yellow. Face and occiput yellow; 

 vertex black ; vertical vesicle slightly excavated in the 

 middle, occiput very convex. Prothorax black or dark 

 brown with yellow spots on the sides and middle; 

 dorsum of the thorax brown, mid-dorsal carinae in part 

 yellow also a broad ante-humeral and a narrow 

 humeral, sides yellow with two well marked oblique 



