36 ENTOMOLOGICAL NEWS. [Jan., '17 



viewed with the microscope, so finely ground and digested, 

 however, that no tissue was distinguishable. 



After a few days of confinement without food or water, fe- 

 males invariably died a premature death, with many eggs in the 

 abdomen unlaid, whereas fed females usually laid all, or nearly 

 all, of their eggs. 



Unfed females were observed to extract eggs from their own 

 abdomens with their mandibles, and to devour them rapidly one 

 after another. The performance of this operation by one in- 

 dividual was witnessed three times in less than one minute. 

 Only those insects which had been confined without food and 

 water for a few days were seen to resort to this source of nutri- 

 ment. In several instances, females were seen trying to extract 

 eggs in this manner without success, the eggs being, presum- 

 ably, too far within the vagina to be reached by the mandibles. 



Since this egg-eating habit is displayed only by unfed individ- 

 uals, it is concluded that hunger is the chief stimulus to this 

 reaction. Scarcity of food for adult Chrysopidae may have 

 been of sufficiently frequent occurrence in the past to account 

 for the development of the preservative instinct exhibited by 

 the females, of eating the eggs. This instinct, however, does 

 not permit the insect to subsist on its own eggs until its abdo- 

 men is emptied of them, as evidenced by the fact of death by 

 starvation with many eggs still in the abdomen. The rate at 

 which eggs are available for extraction by the mandibles is 

 not sufficient to satisfy the demands for nutriment ; however, 

 when food is scarce, this egg-eating habit is doubtless of 

 great preservative value in allowing the females to subsist from 

 one meal of insects to another. 



To summarize: (i) Adults of both sexes feed upon small- 

 er, soft-bodied insects, drink water and discharge solid excre- 

 ment. (2) Unfed females die of starvation, leaving a large 

 portion of their eggs unlaid. (3) Females on the point of 

 starvation eat their own eggs, extracting them from the abdo- 

 men as frequently as they are available a preservative in- 

 stinct. 



Thus Chrysopidae are of even greater economic importance 



