No. 3. ] 



Silkworms in Indii. 137 



first molt, and as the worm increases in size, these h;iirs and tuhercles hecome less 

 noticeable, and the worm generally gets lighter and lighter, until in the last stage it 

 is of a cream white colour. It never becomes entirely smooth, however, as there are 

 short hairs along the sides, and very minute ones, not noticeable with the unaided eye, 

 all over the body. The' preparation for each molt requires from two to three days 

 of fastin" and rest, during which time the worm attaches itself firmly \>y the abdominal 

 prolegs (the eight non-articulated legs under the 6th, 7th, 8th and 9th segments 

 of the body, called prolegs in contradistinction to the six articulated true legs under 

 the 1st, 2nd, and 3rd segments) and holds up the fore part of the body, and sometimes 

 the tail. Iu front of the first joint a dark triangular spot is at this time noticeable, 

 indicating the growth of the new head; and when the term of sickness is over, the 

 worm casts its old integument, rests a short time to recover strength, and then, 

 freshened, supple and hungry, goes to work, feeding voraciously to compensate for lost 

 time. This so-called sickness, which preceded the molt, was in its turn preceded by a 

 most voracious appetite, which served to stretch the skin. In the operation of molt- 

 in°- the new head is first disengaged from the old skin, which is then gradually 

 worked back from segment to segment until entirely cast off. If the worm is feeble, 

 or has met with any misfortune, the shrivelled skin may 3-emain on the end of the 

 body, being held by the anal horn ; in which case the individual usually perishes in the 

 course of time. It has been usually estimated that the worm in its growth consumes 

 its own weight of leaves every day it feeds ; but this is only an approximation. Yet 

 it is certain that during the last few days before commencing to spin it consumes more 



than during the whole of its previous existence Having attained its 



full growth, the worm is ready to spin up. It shrinks somewhat in size, voids most 

 of the excrement remaining in the alimentary canal, acquires a clear, translucent, often 

 pinkish or amber hue, becomes restless, ceases to feed, and throws out silkeu threads. 

 The silk is elaborated in a fluid condition in two lone:, slender, convoluted vessels, 

 one upon each side of the alimentary canal ; as these vessels approach the head they 

 become less convoluted and more slender, and finally unite within the spinnaret, 

 from which the silk issues in a glutinous state and apparently in a single thread. 

 The glutinous liquid which combines the two threads, and which hardens on exposure 

 to the air, may, however, be softened in warm water. The worm usually consumes 

 from three to five days in the construction of the cocoon, and then passes in three days 

 more by a final molt into the chrysalis state. 



" The cocoon. — The cocoon consists of an outer lining of loose silk known as floss, 

 which is used for carding, and is spun by the worm in first getting its bearings. The 

 amount of this loose silk varies in different breeds. The inner cocoon is tough, strong, 

 and compact, composed of a firm continuous thread, which is wound 



. irregularly in short figure-of-eight loops, first in one place and then 

 in another, so that, in reeling, several yards of silk may be taken off without the cocoon 

 turning round. In form the cocoon is usually oval and in colour yellowish, but in both 

 these features it varies greatly, being either pure silvery white, cream, or carneous, 

 green, or even roseate. 



" The chrysalis. — The chrysalis is a brown, oval body, considerably less in size than 

 the full-grown worm. In the external integument may be traced folds corresponding 

 with the abdominal rings, the wings folded over the breast, the antennae, and the eyes 

 of the inclosed insect — the future moth. At the posterior end of the chrysalis, pushed 

 closely up to the wall of the cocoon, is the last larval skin, compressed into a dry wad 



of wrinkled integument. The chrysalis state^continues for from two to three weeks, 



when the skin bursts and the moth emerges. 



