THE SILKWOKM-DISEASE. 129 



the recesses of his desk some five or six silkworms, feed- 

 ing them, in default of mulberry leaves, with leaves of 

 lettuce or salsify. Therefore it is hardly necessary to 

 remind niy readers how the silkworm is born, grows, 

 and is transformed. Coming out of its egg, which is 

 called a grain, because of its resemblance to a small 

 vegetable seed, the silkworm appears in the first fine 

 days of spring. It does not then weigh more than 

 one or two milligrammes. Little by little its size and 

 its activity augment. The seventh day after its birth 

 it rests on a leaf and appears to sleep. It remains 

 thus for nearly thirty hours. Presently, its head 

 moves, as if it did not belong to the rest of the body, 

 and under the skin of this head appears a second 

 quite new head. Just as if it came out of a case, the 

 silkworm disengages itself from its old withered skin. 

 Here are its front feet, there the false feet (faussespattes), 

 which it carries behind. At length the worm is quite 

 complete. It rests a while and then begins to eat. 

 At the end of a few days new sleep, new skin, new 

 shedding of the skin, then a third, and then a fourth 

 metamorphosis. About eight days after the fourth 

 shedding of its skin, the worm ceases to eat, its body 

 becomes more slender, more transparent ; it seeks to 

 leave its litter, it raises its head and appears uneasy. 

 Some twigs of dried heather are then arranged for 

 it to fasten upon ; these it climbs, never to descend 

 again. It spins its cocoon and becomes a chrysalis. 



