73 
Atlantic coast states, but seems less abundant in []linois than 
some other species. Walsh notes an imago taken June 16 eat- 
ing one of the larger caddice-flies, Wacronema zebratum. Kelli- 
cott (’96, p. 111) deseribes the habits of the imago as similar to 
those of fraternus, and says they copulate at rest in trees or 
shrubs. The time of flight seems to be from the latter part of 
May through July. Our Illinois imagos are all from the vicin- 
ity of the Mississippi along the northwestern border of the 
state. Williamson says they frequent the larger rivers and lakes, 
the males being more often found near the water’s edge, the 
females in fields or along roadsides. 
The nymph has been described and figured by Cabot (’72, 
p. 3, Pl. IL, Fig. 4) and again by Hagen (’85, p. 265). The fol- 
lowing brief description is condensed from that of Dr. Hagen. 
The nymph measures 31 mm. in length. 
The mentum of the labium is one third longer than broad; 
the front border of the median lobe is straight, fringed with /ong 
flat scales: the lateral lobes end in a long sharply incurved 
point, inside which the toothed inner margin is concave. Ab- 
domen slowly tapering posteriorly, in outline rather bluntly 
pointed. Ninth abdominal segment three times as long as the 
10th, and a little longer than the 8th. Lateral spines on the 
6th to the 9th segments, those of the 9th as long as the 10th 
segment. Dorsal hooks on the 8th and 9th segments. Ap- 
pendages nearly twice as long as the 10th segment. 
7. Gomphus ventricosus Walsh. 
A widely distributed but rare species in collections. It was 
originally described from Rock Island, [ll., and has since been 
listed from Michigan, Massachusetts, and Virginia. The nymph 
is unknown. 
8. Gomphus fraternus Say. 
This species and the following (erfernus) are closely related 
but specifically distinct. The nymphs of fraternus, if any are 
in our collections, have not been distinguished from those of 
externus, Which is a common species at Havana. Dr. Hagen’s 
