126 Poisonous Caterpillars. 



(says Keaumur, whose observations, in the last century, may 

 be said to have laid the foundation of modern entomology), a 

 single caterpillar goes out first, and, after some hesitation, ap- 

 pears to determine the line of route that is to be followed, by 

 the colony. He is succeeded by a second — a third then appears, 

 and so on, till the whole colony is following the leader in single 

 file ; the line being sometimes thirty or forty feet long. As 

 the food becomes exhausted in the neighbourhood of their 

 nest, they select another centre for their foraging excursions, 

 and establish another set of nests upon the trunk of some fresh 

 tree well suited to their purpose. These nests are slight, but 

 the nest, or rather cocoon, which they construct for the purpose 

 of retiring to when about to enter the dormant state in which 

 the change to the chrysalis, and then to the moth, takes place, 

 is much more compact. The cocoons, being placed close to- 

 gether, slightly resemble in appearance the cells of humble-bees. 



Each caterpillar seals up the opening to his cocoon, or cell, 

 with his own hair, a portion of which loosens and falls off at 

 this period of his existence. These chrysalis-houses are more 

 dangerous to touch than the caterpillars themselves, for when 

 the external web is broken or removed, the disturbed hairs at 

 the opening of each cell are carried about by the slightest 

 wind, and whenever they settle on the skin, a kind of irritation 

 commences very similar to that caused by the sting of a nettle. 

 The boy who recently died from this cause had been climbing 

 a high tree in search of a bird's nest, and no doubt his chest 

 had come in direct contact with a set of cocoons of this kind, 

 for it was in the hands, face, and chest, especially the latter, 

 that the chief seat of irritation, that could not be allayed, had 

 established itself. 



These poisonous hairs, however, which are so injurious to 

 the human skin, do not appear (in spite of all that has been said 

 upon the subject of their being a defence provided against their 

 natural enemies) to be injurious to the birds that prey upon 

 them, as the bodies of these caterpillars have been found in the 

 stomachs of birds that have been shot, without seeming to 

 have caused any internal injury, the stomach of the bird re- 

 maining in a healthy state. One of the handsomest of our 

 European beetles, Calosoma Sycophanta, feeds upon the cater- 

 pillars of the pine-species, C. Pityocampa, following them 

 among the branches of the pine, where it destroys vast numbers 

 of them. 



There are also caterpillars that feed upon them ; these car- 

 nivorous caterpillars being termed by the French vers assassins. 

 The procession caterpillar does not attempt to escape from his 

 unnatural brother, but submits passively to his fate — fascinated, 

 perhaps, in some way, like the bird that becomes paralyzed 



