15 
cocoon and dissolves the hard, gummy lining. Then, by a forward and 
backward motion, the prisoner, with crimped and damp wings, gradu- 
ally forces its way out; and the exit once effected, the wings soon ex- 
pand and dry. The silken threads are 
simply pushed aside, butenough of them 
get broken in the process to render the © 
cocoons from which the moths escape 
comparatively useless for reeling. 
The moth is of a cream color, with more 
or less distinct brownish markings across 
the wings, as in Fig. 4. The males have 
broader antenne or feelers than the fe- 
males, and may be, by this feature, at 
once distinguished. Neither sex flies, but the maleis more active than 
the female, and may be easily recognized by a constant fluttering motion 
of the wings, as well as the feature mentioned above. They couple soon 
after issuing, remaining coupled during several hours, and in a short time 
after separation the female begins depositing her eggs, whether they 
have been impregnated or not. Very rarely the unimpregnated eggs 
have been observed to develop. 
Fic. 4.—Silk-worm moth, male (after Riley). 
VARIETIES OR RACES. 
As before stated, domestication has had the effect of producing nu- 
merous varieties of the Silk-worm, every different climate into which it 
has been carried having produced either some changes in the quality 
of the silk, or the shape or color of the cocoons, or else altered the 
habits of the worm. 
Some varieties produce but one brood in a year; such are known as 
Annuals. Others, known as Bivoltins, hatch twice in the course of the 
year; the first time, as with the Annuals, in the early spring, and the 
second, eight or ten days after the eggs are laid by the first brood. 
With Bivoltins the eggs of the second brood only are kept for the next 
year’s crop, as those of the first brood always either hatch or die soon 
after being laid. The Trevoltins produce three annual generations. 
There are also Quadrivoltins, and in Bengal a variety known as Dacey, 
which is said to produce eight generations in the course of a year. 
Some varieties molt but three times instead of four, especially in warm 
countries and with Trevoltins. Experiments, taking into considera- 
tion the size of the cocoon, quality of silk, time occupied, hardiness, 
quantity of leaves required, etc., have proved the Annuals to be more 
profitable than any of the Polyvoltins. The principle difficulties en- 
countered in raising other than the annual races arise from the excess- 
ive heat of midsummer, which causes disease, and the deteriorated 
quality of the leaves as explained in Chapter X. Silk-growers are 
therefore earnestly advised to attempt but one brood per annum ex- 
