FIELD BOOK OF PONDS AND STREAMS 



Fig. 163. — Nymph of Sympetruni rubicundulum, 

 red dragonflies of autumn. 



through the sunny days of September and even late November. 

 Dr. PhiHp Calvert studied the autumn disappearance of 

 species of Sympetrum and he writes, "Observations made over 

 20 years give the latest dates for the appearance of this species 

 on the wing as ranging from October 17th to November 23rd." 



Dragonflies, Subfamily Gomphinae. — Gomphus (Fig. 164, 2) 

 is a common representative of these stream-inhabiting bur- 

 rowers. They have wedge shaped heads and stout 4-jointed 

 antennse. They sprawl or lie almost buried in the soft bot- 

 toms of slow streams and when they finally leave the water 

 they usually crawl out on the fiat shore to shed their skins. 

 Length of nymph, one inch. 



Dragonflies, Subfamily .^schininae. — In this family the 

 nymphs are smooth and slender, often green or marked with 

 distinct color patterns (Fig. 164, i). They have long thin 

 legs and are active climbers among the vegetation of quiet 

 waters. 



The adults are among the largest dragonflies, those which 



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