76 APPLE LEAVES, APHIS LIONS — THEIR CANNIBALISM. 



upon its pedicel, the other was laid upon the surface of a leaf in 

 the vial. Next morning the latter was found flattened, and with 

 only a small portion of fluid remaining in one end, and the plump 

 size and green tinge of the young larvzf showed plainly that he 

 had appropriated the missing contents of this egg to himself, and 

 in a short time he approached the egg and inserting his jaws into 

 it wholly exhausted it of its remaining contents under my eye. 

 We thus see that the young aphis-lion will devour the eggs of its 

 own species if they are placed within its reach. Is it not won- 

 derful that the female knows this fact when no other insect pos- 

 sesses this knowledge ? It would seem as though she had a re- 

 collection of what her own habits were in the larva period of her 

 life, else why does not instinct inform other insects of this same 

 fact, and excite them to similar artifices for placing their eggs be- 

 yond the reach of these destroyers 1 



A cocoon of spider's eggs was now introduced into the vial last 

 spoken of, upoh which the aphis-lion therein became plump and 

 well fed. Three days after this, the other egg elevated upon its 

 pedicel, having been wholly undisturbed, hatched, and the infant 

 larva from its approaching the older one, which was full three 

 times its size, the latter to my astonishment, passively and with- 

 out manifesting the slightest resentment, permitted the newly- 

 born infant to pierce him repeatedly with its jaws until life was 

 extinct. His carcase was then shoved off from the leaf, and aban- 

 doned, little if any of the juices being sucked from it. I can only 

 account for this strange phenomenon — the young and weak de- 

 stroying the strong — by supposing there had been some poisonous 

 quality in the spider's eggs on which the older aphis-lion had fed, 

 which had rendered him diseased and weary of life, for he even 

 seemed to solicit his pigmy kinsman to slay him. Our American 

 species, however, appear to be less inclined to cannibalism than 

 those of Europe, this being the only instance in which I have 

 known one to destroy another, and for several days I have had a 

 Chrysopa and a much larger Hemerohius larva enclosed together 

 and left at times without food, yet they have manifested no incli- 

 nation to molest each other. 



