AQUATIC INSECTS 



Occurrence. — In New England the adults, called "ten- 

 spots," emerge from the last of May to the middle of 

 September (PI. X). 



Fig, 162. — Nymph and adult of the whitetail, 

 Plathemis lydia. 



Whitetails, Plathemis. — The habits of these nymphs (Fig. 

 162) are essentially the same as those of Lihellula. Fullgrown 

 nymphs are about I inch long. 



Occurrence. — Adults emerge from mid-May to late Sep- 

 tember. 



Sympetrum. — These are the small, brilliant red dragonflies 

 which fly about near ponds, alighting on low vegetation or 

 sunning themselves in roadways (Fig. 163). Their striking 

 colors make them well known in autumn when they are active 



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