By) 
the base of the hook, the lobes terminating in an internal tooth 
as long as half their apical width. 
The eyes are small but very prominent, about as in Brachy- 
tron. Behind them the lateral margins of the head extend in 
a ridge to the rather acute hind angles. Back of the middle of 
this ridge is a prominent tubercle. There is another pair of 
tubercles, close together on top of the head. The hind margin 
is broadly concave. 
Abdomen with lateral spines on segments 5 to 9, increas- 
ing in length posteriorly, those of 9 about half as long as the 
10th segment. 
Superior and inferior appendages equal, obtusely pointed, 
male scale equilaterally triangular, its apex shining black, 
rounded. Dorsal hooks on segments 8 and 9 and sometimes on 
7; represented on the other segments by median ridges. 
Il. Eptascuna. 
This genus is intermediate in structure between Nasiwschna 
and 4schna, the three genera which follow between it and 
“éschna representing a branch line of development. The 
nymph resembles that of Nasiwschna and probably has similar 
habits, but it is without dorsal hooks. The adult may be recog- 
nized by the structure of the anal loop and other details of 
wing venation. We have but one species in this country. 
Epieschna heros Fabr. 
This, the largest of our dragon-flies, is not common in IIli- 
nois, though Mr. A. H. Mundt (’82) has recorded the passage of 
a swarm of them towards the southwest over Fairbury, Living- 
ston county. The air, he says, was literally alive with them; 
few alighted, and on the following day only a few stragglers 
remained. Anax Junius was, and continued to be, the common 
local eeschnid species. Heros is found from Quebec to Mexico; 
thence west to the Mississippi River. The Illinois localities are 
Rock Island, Quincy, Bloomington,and Urbana, and the extreme 
dates April 23 and September 1, Williams says it often enters 
