DISEASES OF INSECTS. 905 
The cultivators of the sz/k-worm in France have given 
names to several diseases to which that animal is subject. 
One is called La Rouge, and is supposed to be occasioned 
either by too great heat, or by too sudden a transition from 
cold to heat. It takes place when the caterpillar is first 
hatched; which lives perhaps, but in a very sickly state, 
till it should spin its cocoon and assume the pupa, when it 
expires. Another degree of the same disease is called Les 
Harpions or Passis. A second distemper of this animal 
is Des Vaches, Le Gras or La Saune: this is a mortal dis- 
ease, supposed to be of a putrid nature, and produced 
by mephitic air; it shows itself after the second mouit, 
but rarely after the subsequent ones. When a caterpil- 
lar is first attacked, changing the air may prove a remedy ; 
but when the disease has made progress, it is best to 
burn or bury them, since if the poultry pick them up 
they might be poisoned by them. A third disease of 
silk-worms is called Les Morts Blancs, or Tripes, which 
is also occasioned by impure air, when the leaves the 
animal feeds upon are heaped so as to produce fermen- 
tation. ‘The caterpillars attacked by it die suddenly, 
and preserve after their death the semblance of life and 
health. Too great heat, whether artificial or natural, 
occasions La Touffe, another disease, which, when the 
heat continues long, destroys all those that are arrived 
at their last stage of existence in their larva state. Black 
points scattered over different parts of the body, or livid 
and blackish spots in the vicinity of the spiracles, fol- 
lowed by a yellowish or reddish tint, are symptoms of a 
fourth malady, called La Muscardine. After this the ani- 
mal soon dies, and becomes mouldy, but does not stink. 
