100 FALSE PARASITES 



winter- time, by gathering fruit, as strawberries, 

 which grow under the oak-trees, by collecting 

 grass, litter, or the fallen leaves of forests. The 

 disease^ which follow are violent inflammation of 

 the eye, erythema of the eyelids, blenorrhoea, 

 coughing, inflammation of the throat and the 

 lungs, violent itching and scalding eruptions of 

 the skin (nettle-rash), and general fever. The 

 question is, whether the above-described dust — 

 which is found, according to Nicolai, more partic- 

 ularly on the edges of the black shields of each 

 segment lininor the shields with a brownish-red and 

 delicate border, and which is velvet-like, very 

 fine, lustrous, and soft, and which can t)e loosened 

 and shaken away at the caterpillar's pleasure — be 

 merely a mechanical, or also, at the same time, a 

 chemical irritant ; opinion differs somewhat. 



Treatment and Prophylaxis. — The destruction 

 of the caterpillars by burning and singeing them 

 by means of wisps of straw, or by sweeping them 

 off the trunks of the trees and crushing them on 

 the ground, is always dangerous to the operator, 

 since the dust is dispersed in the air. Obstacles 

 to their migration, such as coal-tar, tarred paper, 

 and digging trenches round the trees, are of no 



