lOO INSECT LIFE. 



2. The food of May-flies — can you find any that 

 are catching other insects or that are feeding on 

 plants? 



3. The young of May-flies live in the water. Try 

 to observe the emergence of the insects from the 

 water. 



4. If you succeed in observing the emergence of 

 the winged insect from the water, collect the empty 

 nymph skin and, if possible, the winged individual 

 that emerged from it. These should be preserved 

 together in your collection ; they will serve to con- 

 nect the adult with its early stages. 



5. May-flies differ from all other insects in that 

 they shed the skin once after they are able to fly. 

 The winged May -fly when it emerges from the 

 water is not a fully developed adult, but is what is 

 termed a siibimago. The subimago state is of short 

 duration ; sometimes it lasts only a few minutes, but 

 in other species it lasts twenty-four hours or more. 



Watch the May-flies that are resting on plants or 

 other objects near the shore and try to observe the 

 molting of the subimago. If you succeed, collect 

 the adult or imago and the empty subimago skin, 

 and preserve them together in your collection. Even 

 if you fail to observe the molting, you ought to be 

 able to collect subimago skins if the May-flies are at 

 all abundant. 



6. Endeavor to observe the laying of the eggs. 

 Some May-flies lay their eggs in masses; specimens 

 are often found in which there project from the cau- 

 dal end of the body two parallel, subcylindrical 

 masses of eggs, for in these insects the two oviducts 

 open separately. 



