15S Processionary Caterpillars 



its long axis, as tliough tlieir goal was the extreme summit of the 

 hill. 



These caterpillars are known as Processionary Caterpillars 

 {Cnethocampa pityocanipa) . They are something over two inches in 

 length, covered with fine barbed hairs, bluish black above with 

 brownish \-enow projections on each segment. These hairs, and the 

 dust from the " nests " are intensely irritating, causing a very severe 

 inflammation of the skin in human beings. It is even said that death 

 has been known to result from handling these caterpillars and their 

 nests. 



I suppose that, like our Fox moth larvje, they are liable to attack 

 by ichneumons ; a text-book I have referred to says that their great 

 enemy is a large green beetle (Calosoma sycophcuita). 



However that may be, neither the ichneumons nor the beetle 

 in this particular case appeared to be doing their unpleasant duty 

 very efficiently The caterpillars swarmed over the land, and, 

 unless something unforseen happened, it appeared likely that they 

 would entirelv destroy every fir-tree in the district. 



I have no doubt that they are noxious to birds and small 

 mammals alike, and are severely left alone. Humans daren't go 

 near their nests, and on the high ground, at any rate, they appeared 

 to enjo}' a complete immunity from foes of every kind except winter 

 and rough weather. 



It seemed likely to me that they would only perish in the end 

 by starvation, having exhausted their food supply by killing ever}' 

 hr tree in the district. 



I have already described the huge webs, or cocoons, so 

 conspicuously l^uilt on the fir trees — sometimes several on one tree, 

 and seldom a tree without at least one. As we came down the hill, 

 it occurred to me that I would like to see the inside of one of these 

 nests. I did not then know how poisonous are the dust and debris 

 from the webs, but a previous experience with comparatively harm- 

 less hairy caterpillars in England had taught me caution. 



I selected a large cocoon on a iir tree growing near the road, and 

 approached it from the windward side, my hands being encased in 

 gloves. Then with one hand, and the point of the umbrella, I 

 dissected the cocoon open. The cocoon was securely fastened 

 completely round a terminal shoot on a lateral branch, some four or 

 five feet from the ground. The web, in fact, enclosed a considerable 

 piece of growing hr. The covering was tough and well matted 

 together. When at last the " nest " was opened, and its contents 

 fully exposed, I found it crowded with caterpillars (which 

 appeared to be half-grown editions of the same species that was 

 processioning on the road) , together with a handful of the broken-up 

 fragments of the needles of the enclosed fir, which had been three- 

 parts stripped by this time. 



The ingenious parents of these caterpillars had, I suppose, 

 laid their eggs in autumn, and had then not only constructed an 



