DRAGONFLIES AND DAMSELFLIES IN PONDFISH CULTURE. 19! 
curled up in the sun, half or three-fourths of an inch above the water. Twenty-five 
such teneral Ischnuras were seen close to their exuviee upon the pond-lily leaves of pond 
3 On the afternoon of July 28, 1917, but not a single Enallagma. Nor have the exuviz 
of the latter ever been found in such places around the Fairport ponds. 
The nymphs of Argia masta putrida often crawl long distances over the land and 
then up the trunk of a tree and are the only damselfly exuvie found in such positions. 
This leads naturally to the second consideration. 
2. DisTANCE TRAVELED.—The distance to which the nymphs crawl before trans- 
forming varies greatly, not only for the different species, but also for different individuals 
of the same species. Some nymphs, like those of Perithemis domitia and the two Sym- 
petrums, were always found upon rush or grass stems standing in the water, often at 
quite a distance from the shore. Others, like Anax, Alschna, and Erythemis, were 
close to the shore, sometimes over the water, and sometimes over the land, but never 
very far from the water’s edge. Lubellula luciuosa, Epicordulia, and Plathemis, on the 
other hand, crawl much farther and sometimes go a long distance. In the first count, 
1 Plathemis, 5 Epicordulia, and 47 L. luctwosa crawled up the bank of the pond, across 
the cinder road, up a dirt bank bordering the road, and into the grass field, the entire 
distance being 50 or 60 feet. The other individuals of these species were all found 
between the road and the water’s edge. 
3. Lack OF PROTECTIVE INsTINCcT.—While instinct may guide the nymph to the 
shallow and sunny side of the pond, it apparently fails him in some other directions. 
There were two red-winged blackbirds’ nests in the cat-tails and crex grass on the shore 
of pond 2, where the second count was made. Twenty-five nymph skins were taken 
within a radius of 6 inches of one of these nests, three of which were actually fastened 
to the sides of the nest itself, and seven were found within a similar radius of the other 
nest. The young birds had only just left the nests and were still in the immediate 
vicinity, so that some of the nymphs must have transformed while the nests were still 
occupied. 
4. RELATIVE ABUNDANCE OF SPECIES.—From the counts above recorded it appears 
that L. luctuosa is the most abundant species, and also that it emerges before the others. 
Its time of greatest abundance is during the last of June and the first of July, when it 
constitutes over go per cent of the dragonfly fauna of the ponds. Although it keeps up 
a good percentage and remains throughout the season more numerous than any other 
single species, it quickly loses its relative predominance and steadily declines during 
the latter part of the season, until by the middle of August it is only a little more 
numerous than E. simplicicollis. 
On the other hand the latter does not begin to appear until Juctuosa has reached its 
maximum. It then rapidly increases, while /uctuosa is decreasing, and its time of greatest 
abundance is the latter part of July, following which it declines through August. 
Tramea, Anax, and Aeschna did not really begin to appear until the middle of July 
and then steadily increased through the remainder of the season, until by the first of 
September, together with Epicordulia, they were about the only species left. In 1917 
a very much larger number of Anax and A’schna exuviz were found early in the season, 
by the last of June or the first of July; but the imagos were no more numerous than 
during the preceding year, because they scatter immediately after emergence. Both 
species must return to deposit their eggs either in the pond where they were hatched or 
