INSECT ORDERS 241 



Order — Ephemerida 



These are the May flies which come out in the late spring or early 

 summer by the thousands. They join in a dancing flight up and down 

 in the air which ends in mating, after which the females deposit their 

 eggs on or in the water and then die, usually no more than twelve hours 

 after attaining adulthood. They usually emerge at about dusk and are 



Photo by Winchester 



Fig. 17.1. The May fly. After spending up to three years in the water as immature 

 forms, the adults emerge and live but a day or so, only long enough to reproduce. 



often attracted to lights, but they may meet their doom in a flame before 

 fulfilling their destiny. The naiads live in the water and develop as long 

 as three years before becoming adults. 



They have two pairs of membranous wings, but the hind pair are 

 much smaller than the front pair. There are three long projections, 

 cerci, from the posterior tip of the abdomen which are longer than the 

 body itself. Metamorphosis is incomplete and, since they live such a 

 short time as adults, the mouth parts are vestigial and entirely useless so 

 far as feeding is concerned. 



