75 
Rock River, in northern [linois; from the Sangamon, in the 
central part of the state; and from the Big Muddy at the south. 
Transformation was first observed May 21. Mr. Needham’s 
notes of his observations on this species while at Havana are 
as follows: ‘Transformation takes place in the night or very 
early morning. The nymph crawls but a little distance (one to 
two feet) out of the water before fixing itself for emergence. I 
have found exuvie on bridge piers and on willow stumps, and 
have taken imagos emerging in such places at about six o’clock 
on several mornings.” 
The strong-flying imago was not uncommon at Havana 
during July, 1896. The males were frequently seen chasing 
each other over the open river, or sitting at rest on the sand at 
the bank with the abdomen elevated and the wings declined 
until their tips touched the sand, in a position of great alert- 
ness. The females fly less openly. One female captured in the 
weeds at the bank, deposited for me in a watch-glass of water 
in a few minutes’ time about 5,200 eggs. This number is an 
estimate from a partial count. 
An observation on the food of the imago was made by Mr. 
Needham, who found on shore a female fraternus engaged in 
eating a teneral imago of Mesothemis simplicicollis. 
Examples of the nymphs collected in June were placed in 
breeding-cages immersed in the water of Quiver Lake beside 
the field laboratory of the Biological Station. They remained 
without transforming, and at the close of the season’s work, 
September 28, seventeen nymphs, nearly the original number, 
were still alive in the cage. 
About the middle of July, after a severe rain storm, sev- 
eral dead males of this species were picked up from the guards 
of cabin-boats along the Havana river-front. 
The imago is reported from Illinois, Nebraska, Kansas, 
Texas, and New Mexico. In Illinois it has been taken in Hen- 
derson county, as well as at Havana and Rock Island.* 
*According to Calvert, the imagos described as externus by Kellicott ('99) and 
Williamson (oo) are G. crassus Hagen, a species not yet found in Illinois, which is 
quite unlike ex/ermms in the form of the terminal appendages of the male. 
