CHAPTER I. 
Y PHYSIOLOGY AND LIFE-HISTORY OF THE SILK-WORM. 
: The Silk-worm proper, or that which supplies the ordinary silk of 
commerce, is the larva of a small moth known to scientific men as Seri- 
cariamort. Itis often popularly characterized as the Mulberry Silk- 
worm. Its place among insects is with the Lepidoptera, or scaly-winged 
insects, family Bombycida, or spinners. There are several closely allied 
species, which spin silk of different qualities, none of which, however, 
unite strength and fineness in the same admirable proportions as does 
that of the mulberry species. The latter has, moreover, acquired many 
useful peculiarities during the long centuries of cultivation it has un- 
dergone. It has in fact become a true domesticated animal. The qual- 
ity which man has endeavored to select in breeding this insect is, of 
course, that of silk producing, and hence we find that, when we com- 
pare it with its wild relations, the cocoon is vastly disproportionate to 
the size of the worm which makes it or the moth that issues from it. 
_ Other peculiarities have incidentally appeared, and the great number 
of varieties or races of the Silk-worm almost equals those of the domes- 
tic dog. The white color of the species, its seeming want of all desire 
_ to escape as long as it is kept supplied with leaves, and the loss of the 
power of flight on the part of the moth, are all undoubtedly results of 
domestication. From these facts, and particularly from that of the 
_ great variation within specific limits to which the insect is subject, it 
_ will be evident to all that the following remarks upon the nature of the 
_ Silk-worm must necessarily be very general in their character. 
The Silk-worm exists in four states—egg, larva, chrysalis, and adult 
or imago—which we will briefly describe. 
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DIFFERENT STATES OR STAGES OF THE SILK-WORM, 
THE Eac.—The egg of the Silk-worm moth is called by silk-raisers 
the “seed.” It is nearly round, slightly flattened, and in size resem- 
bles a turnip seed. Its color when first deposited is yellow, and this 
color it retains if unimpregnated. If impregnated, however, it soon 
— acquires a gray, slate, lilac, violet, or even dark green hue, according 
to variety or breed. It also becomes indented. When diseased it as- 
sumes a still darker and dull tint. 
_ Near one end a small spot may be observed. This is the micropyle, 
and is the opening through which the fecundating liquid is injected 
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