CARNIVOROUS BUTTERFLIES — CLARK 479 



sions large numbers ot" larvae had disappeared in a mysterious 

 manner. 



He then placed about 50 larvae on as many sprigs of thyme so 

 as to keep them separate and under very close observation. On 

 August 11, many of the larvsB having passed their third molt, when 

 they cease feeding on thyme, he started to investigate what rela- 

 tion there might be between the larvae and ants, thinking that in 

 all probability they might feed either on the larvae or pupae of 

 the latter. 



He had previously found that after the third iriolt the larvae 

 persistently refuse to remain on thyme blossoms, or indeed on any 

 other part of the plant, and appear to have a tendency to hide in 

 the ground. Although thyme and various other plants were sup- 

 plied to them, they refused to feed, so, leaving them with a grow- 

 ing plant of thyme and keeping them under conditions as natural 

 as possible, trusting they would hibernate in that stage, he left them 

 undisturbed ; but subsequently nothing more was seen of them. 



Pie at first selected one of the larvae after the second molt to 

 experiment with, as he found that after the third molt they do not 

 attack each other. Their cannibalistic habits only exist during the 

 first three stages. 



He supplied this larva with an ant's cocoon with one end removed. 

 It at once began eating it. He then placed the two objects under 

 the low power of the microscope to watch carefully the proceedings, 

 which were interesting. He watched it feeding on the jellylike sub- 

 stance of the pupa, as well as the cocoon, which it ate in the same 

 manner as it would a leaf, by biting the edge. 



So far this seemed satisfactory, as he thought he had found the 

 right food for the larvae in their subsequent stages ; but this proved 

 not to be the case. 



Having found a dead L. anon larva, he placed it in a box with 

 some ants, which immediately seized hold of it, apparently intend- 

 ing to kill it. 



He then put a living larva in another box with four ants {Formica 

 flaim)^ and expected them to treat it in the same way, but was sur- 

 prised to find them act quite the reverse. They all immediately lan 

 to it and, waving their antennae over and upon it, at the same time 

 closed their jaws, and then apparently smelt and licked it, and 

 seemed particularly attracted to the hinder part of its back, about 

 the tenth segment. First one and then another of the ants would 

 run over the larva, and then stop to lick that part of its back. He 

 then noticed that a tiny bead of moisture appeared, and (me of the 

 ants touched it with its mouth, which instantly caused the bead to 

 disappear. He afterwards placed both hirva and ants under the 



