164 DRAGONFLIES OF NORTH AMERICA 
25. Macromia Rambur 
These are fine clear-winged dragonflies of brownish color and very 
robust form. The top of the vertex is a double cone, with the two 
apices rather sharply pointed. The legs are black. The wings are 
hyaline. A girdle of yellow encircles the thorax and there is a saddle of 
yellow upon the dorsum of the seventh abdominal segment more or less 
well defined. 
Most species seem to prefer the larger streams over which they sweep 
boldly and erratically here and there, betaking themselves often in 






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Fig. 33. Wings of Macromia pacifica. 
high flights above the neighboring tree tops. Their season of greatest 
activity is midsummer and they are most in evidence on clear hot days. 
The females oviposit unattended by the males. 
Williamson has studied the species of this genus occurring in Indiana, 
and has this to say about their habitat and habits (’15, p. 386): “The 
Wabash River at Bluffton during recent years has been overrun at the 
ripples by willow herb, so the river in summer is reduced to a succession 
of pools of greater or less length. On the banks Hibiscus militaris has 
become throughly established at the water’s edge. These pools seem 
to be an ideal home for the Macromias. 
“Individuals follow the same track over and over, crossing the river 
at a certain point, returning over a certain patch of willow herb, turning 
out from the shore line at a certain clump of Hibiscus, and going and 
coming over the same or nearly the same course, and not following the 
pools in a circular manner. Moreover, individuals of successive gener- 
ations have followed the same course as their predecessors, as I have 
observed at the pools where I have found individuals most numerous, 
