. 40 
To avoid the disease one should carefully follow the fundamental rules 
already laid down (Chapter IV), though even then circumstances may 
be against the silk-raiser and the crop be lost through no apparent 
fault of his. 
GRASSERIE. 
This disease is of little importance, and has therefore received but 
little attention from scientists. It is thus described by Maillot :* 
‘‘In the middle of a school of worms in good condition it is not rare, 
as a molt approaches or just before the spinning begins, to find here 
and there some worms which crawl slowly, and have a shining, stretched, 
thin skin; the body is of a bright yellow in the yellow, and of a milky 
white in the white races; a troubled liquid transudes through the skin ; 
soiling the food and the worms over which the diseased subjects pass. 
* * * A moist, cold, stagnant air seems to favor the occurrence of 
grasserie. The disease is not contagious, * * * nor does it appear 
that it can be transmitted by heredity. From this point of view there 
is nothing to be feared, unless a great number die of the malady, in 
which case it will be imprudent to use the stock for reproduction.” 
Victims of this disease should be removed as soon as discovered, as 
they are apt to crawl into the branches and soil the cocoons spun by 
other worms. 
Prefacing the next chapter we may draw the following conclusions 
from what has been said: Grasserie is never hereditary, as the victim 
never dies later than in the chrysalis state, and the disease can never 
originate in the moth. This is equally true of muscardine, provided 
the moths be not mingled with worms covered with the spores of the 
Botrytis. In such a ease the moth might also catch the disease and its 
general debility decrease the vigor of its progeny. Flaccidity is hered- 
itary in an indirect manner, a debility springing from the affection of 
the parent rendering its issue more apt to succumb to disease. And 
finally, pébrine is hereditary in its true sense, the corpuscles passing 
from the mother through the egg to the next generation. In the pro- 
duction of eggs, then, we need look for flaccidity and the pébrine only, 
the other diseases not entering into the consideration. 
* Legons, etc., p. 111. 
