2l8 FIELD ZOOLOGY. 



when the insect is resting on some grass stem, the hind 

 wings are plaited and the front wings lie flat on the back. 

 The antennas are thread-like and reach far out in front of 

 the head. 



None of the stone flies "has a well-known life history. 

 They seem to reproduce by a metamorphosis much like 

 that of the dragon flies. Their food habits are not 



^^-a^^:^-. \ 



A B 



Fig. 89. — Nymph and adult of a stone fly, Pteronarcys regalis. A , nymph (after 

 Newport) ; B, imago. (Slightly reduced. Folsom.) 



certainly known ; they probably eat other forms of aquatic 

 life; but some observers who have made a somewhat 

 extended study of them, say that they also seem to be 

 scavengers, eating decaying organic matter. Small stone 

 flies are less than one-fourth of an inch long, while the 

 larger species are two inches long. Here is a field for 

 investigation for someone who likes to be much in the 

 open, and who is in sympathy with life in its manifold 

 phases and activities. 



