258 BULLETIN OF THE BUREAU OF FISHERIES. 
distances into the fields and woods. They are quiet and remain well concealed, so that often when none 
can be seen a sweep of the net through the vegetation will reveal them. 
ENALLAGMA SIGNATUM (Hagen). 
Agrion signatum Hagen, Snyop. Neurop. N. A., 1861, p. 84. 
This is the only orange-colored species of the genus found about the ponds, and this makes it con- 
spicuous while flying, as wellas atrest. The males and the two sexes when paired frequent the lily pads 
and similar water vegetation, sometimes long distances from shore. It is nearly as active and restless as 
geminatum and, like the latter, flies close to the water, making it difficult to catch. The species is 
common along the slews of the river as well as around the ponds and probably plays an important part 
in the life of those localities. 
HETARINA AMERICANA (Fabricius). 
Agrion americana Fabricius, Ent. Syst. Suppl., 1798, p. 287. 
This species frequents the neighborhood of flowing water, and hence is never found around the 
quiet ponds, but only on the river where the current runs swiftly. It is not very common anywhere 
near Fairport. 
ISCHNURA VERTICALIS (Say). 
Agrion verticalis Say, Jour. Acad. Nat. Sci., Phila., 1839, p. 37. 
This is the most common damselfly around the ponds, appearing first in the spring and disappearing 
last in the fall. It frequents the thick grass and other vegetation to quite a distance from the margins 
of the ponds. The females are dimorphic; that is, of two different colors, and the black and the orange 
are about equally numerous. Both sexes are weak fliers and can be caught easily in the hands. The 
nymphs are abundant in all the ponds, and the stem of nearly every water plant projecting above the 
surface is covered with their skins. The species can be raised with little trouble if suitable aquaria 
are provided with the stems of rushes or similar water plants projecting above the surface. As the 
tables show, the nymphs are eaten not only by the fish but also by the larger dragonfly nymphs. There 
are probably a number of overlapping broods every season. 
LESTES EURINUS Say. 
Lestes eurinus Say, Jour. Acad. Nat. Sci., Phila., 1839, p. 36. 
This is a large and stout species and has been found thus far only at the eastern end of the ponds; 
its nymphs have been taken in ponds 4 and 8, but not elsewhere. The imagos are associated with 
those of rectangularis and unguiculatus, and late in the afternoon the three species can sometimes be 
obtained in one sweep of the net. In spite of its size this species is a weak flier, but is an omnivorous 
eater. Two females were captured with partly eaten, brown moths in their mandibles; others were 
found eating butterflies, small caterpillars, and even teneral Enallagmas and Ischnuras. 
LESTES RECTANGULARIS Say. 
Lestes rectangularis Say, Jour. Acad. Nat. Sci., Phila., 1839, p. 34. 
This is a very long and slender species and may be recognized by these characters. It is the most 
common species around the ponds and was taken also along the river and at both Sunfish Lake and 
Patterson Lake on the Illinois side. It is rather more of a woodland species, but is found as well in the 
open, especially where there is rank vegetation to furnish shelter. It is not as omnivorous as the pre- 
ceding species, but feeds largely on gnats and midges. 
LESTES UNGUICULATUS Hagen. 
Lestes unguiculatus Hagen, Synop. Neurop. N. A., 1861, p. 70. 
The smallest of the Lestes species and found along only the eastern end of pond 4, where it is fairly 
common. No nymph that could be identified with this species was found in any of the ponds, 
although it is probable that the imagos referred to deposit their eggs in the ponds. 
