54 DRAGONFLIES OF OHIO. 



On abdomen less sharph^ defined. The abdomen is 

 stout 8 and 9 somewhat expanded ; the appendages 

 are long, j'ellovv, acute; the vulvar lamina nearly 

 as long as 9, divided to the base, branches nearly 

 cylindrical, pointed, apexes bent outward and upward, 

 claw^like. 



It has not been taken later than June 20 in Central 

 Ohio. 



GOMPHUS, Leach. 



This genus is well represented in our fauna; four- 

 teen species have been taken and a few more are sure to 

 be added in the future. 



Baron De-Selys has arranged the species in groups 

 defined as follows : 



I Group, (Indian). 



II Group. Front of thorax with six broad black 

 bands; 7, 8 and 9 much dilated; membranule moder- 

 ate. Anal appendaaes of the male black. 



III Group. Front of the thorax yellow with six 

 lines or bands, more or less broad ; segments 7, 8 and 

 9 somewhat dilated ; membranule ver^' small ; anal ap- 

 pendages black, superiors as long as 9, inferiors almost 

 as long. 



IV Group. Front of thorax olivaceous, with 4 or 6 

 lines or bands, brown, more or less distinct; segments 

 7 and 8 moderately expanded ; anal appendages yellow 

 or light brown, superiors as long as lU, inferiors 

 nearly as long. 



Y Group. Front of thorax with an interrupted, 

 mesothoracic semi-collar and two cuneiform spots 

 (stripes) yellow ; sides yellow with two black rays, 

 confluent at two points ; pterostigma short, black ; 

 face mostly black ; anal appendages browm, superiors 

 longer than the 10th segment. 



YI. Group. Front of the thorax black with two 

 antehumeral wide bands and a superior antehumeral 



