42 
of Lake Geneva, Wisconsin, within ten miles of the Illinois 
line, September 2 and 5, about the summer resort cottages and 
along the lake shore. In New York it has been taken from 
August 28 to September 22; in Nova Scotia, July 26. Cabot 
described and figured (781, p. 23; Pl. IL, Fig. 2) a nymph 
taken at the same time and place as imagos determined as 
“E). “ eremitica,” and assigned it by supposition to that species. 
Eremitica is an erroneous writing of eremita, which is a syno- 
nym of clepsydra. 
The nymph of clepsydra differs from all other known 
“Eschna nymphs in having recognizable lateral spines on the 
fifth abdominal. It is otherwise similar to constricta, and may 
be distinguished especially by the following characters given 
by Cabot (81, p. 37) from full-grown nymphs of both sexes 
from Hermit Lake in New Hampshire, mouth of Red River of 
the North, and Minnesota: “ Hind angles of head oblique, proc- 
esses long, equal, sharp, tips bent a lttle outwards, inclosing 
less than a right angle; lateral appendages two thirds the 
length of the middle one ; female valves not quite reaching tip 
of segment.” 
2. Alschna constricta Say. 
This is one of our more common dragon-flies, appearing on 
the wing in Illinois after midsummer, and disappearing only 
with the autumnal frosts. It ranges over the entire northern 
part of the United States, and from Labrador into Siberia, 
being apparently less common throughout the Mississippi 
valley than on the north Atlantic and north Pacific slopes. 
The Illinois specimens are from various localities in the cen- 
tral and northern parts of the state. Van Duzee (’97) found 
it most abundant along the meanderings of small brooks in 
hilly country. 
Our nymphs were collected in a small ditch at the west 
end of Lake Geneva, Wisconsin, in August, and from a little 
streamlet in the Mississippi bluffs near Savanna, Illinois. We 
also have a half-grown nymph from Pine Lake, near Charle- 
