10 



THE CULTURE OF THE MULBERRY SILKWORM. 



The chrysalid state is in certain respects a sleep and in others a period 

 of great activity, in which the entire being is transformed. Wings, 

 antenna?, reproductive organs, and legs are all now developed. This 



Fig. 3.— The chrysalis: a, silkworm completing its cocoon; b, cocoon and chrysalis— cast-off skin of 

 larva beneath; c, back view of chrysalis: d, side view of chrysalis. | Redrawn from Maillot.) 



state lasts from eighteen to twenty days, according to the temperature. 



Then the metamorphosis is complete, and the sheath breaks in the 



region of the head and out of the old case the moth or perfect insect 



issues. 



THE MOTH. 



The larva in spinning the cocoon leaves one end less dense, so that 

 the threads open freely to permit the egress of the moth. By the aid 

 of an alkaline fluid the moth sof- 

 tens and parts the threads and lib- 

 erates itself. 



The moth (fig. 4) comes out of 

 the cocoon, as the larva out of the 

 ecrg^ in the early morning hours. 

 It has a distinct head, thorax, 

 and abdomen, four wings, two 

 comb-shaped antenna?, three pairs 

 of legs, and a pair of compound 

 eyes. 



Shortly after emerging, the 

 moth deposits a liquid substance, 

 generally white, sometimes color- 

 less and sometimes reddish, and 

 then the union occurs, lasting sev- 

 eral hours, after which the eggs 

 are laid either immediately or in 

 the course of four or five hours. 



A gelatinous substance supplied by two glands near the extremity 

 of the oviduct rovers the eggs as they come out, and causes them to 

 adhere to the substance on which the} T are laid. 



the male; b, the female 



