CATERPILLARS. 153 



only a portion of tlie branch. In none of their operations 

 did they seem to be subject to any discipline, each indi- 

 vidual appearing to work, in perfecting the structure, from 

 individual instinct, in the same manner as was remarked 

 by M. Huber, in the case of the hive-bees.* In making 

 such experiments, it is obvious that the species of cater- 

 pillars experimented with must feed upon the same sort of 

 plant. (J. E.) 



The design of the caterpillars in rolling up the leaves 

 is not only to conceal themselves from birds and predatory 

 insects, but also to protect themselves from the cuckoo- 

 flies, which lie in wait in every quarter to deposit their 

 eggs in their bodies, that their progeny may devour them. 

 Their mode of concealment, however, though it appear 

 to be cunningly contrived and skilfully executed, is not 

 always successful, their enemies often discovering their 

 hiding-place. We happened to see a remarkable instance 

 of this last summer (1828), in the case of one of the lilac 

 caterpillar which had changed into a chrysalis within the 

 closely-folded leaf. A small ichneumon, aware, it should 

 seem, of the very spot where the chrysalis lay within this 

 leaf, was seen boring through it with her ovipositor, and, 

 introducing her eggs through the punctures thus made 

 into the body of the dormant insect. We allowed her to 

 lay all her eggs, about six in number, and then put the 

 leaf under an inverted glass. In a few days the eggs of 

 the cuckoo-fly were hatched, the grubs devoured the lilac 

 chrj^salis, and finally changed into pupae in a case of yellow 

 silk, and into perfect insects like their parent. (J. E.) 



* See p. 100. 



