FIELD BOOK OF INSECTS. 



brown body marked with yellow, but the old males are 

 powdered with white. 



Three of our most beautiful small species 

 Celithemis 



belong to this genus. C. epomna (Plate 

 XII) is adult in late June and early July along the borders 

 of ponds and in the neighboring fields. C. elisa has a 

 small rounded spot of brown on each front wing just 

 beyond the place where eponina has a brown band. C. 

 ornata (Plate XII) is found along the Atlantic coast from 

 Maine to Florida. 



Many of the species of this large genus 

 Sympetrum J f 6 



have brilliant red bodies. They frequently 

 fly far from their marshy home. The only one of our 

 common species which has wing markings is 6*. semicinctum 

 (Plate XII). 



PLECOPTERA 



All observant trout fishermen have noticed on the stones 

 in rapid streams hordes of flat larva? (nymphs) clinging 

 tightly or scuttling from place to place. They usually 

 belong to this group (see Plate XIII), as may be told by 

 the two tail filaments, two tarsal claws and the thread- 

 like gills, if any, at the bases of the legs. There is only 

 one family, PERLID^;, the common name being Stone- or 

 Salmon-flies. They never have gills along the sides of 

 the abdomen, although there may be gills at the bases of 

 the tail filaments; the thoracic gills are not large and the 

 smaller species have none at all, depending upon the 

 thinness of the skin on their underside for the transfer 

 of oxygen. Since the breathing apparatus is so poorly 

 developed, they are largely confined to well-aerated water. 

 They feed upon other aquatic animals and are eagerly 

 eaten by trout, making excellent wet bait. Especially 

 during the first warm days of spring, the full-grown nymphs 

 crawl out on stones or logs and the adults leave the 

 nymphal skin, which, complete even to the lining of the 

 main tracheae and of the fore-gut, is hooked to the molting 

 place. The adults are gray or greenish, usually .with two 



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