2( « i 



SOME SOUTH INDIAN INSECTS, ETC. [CHAP. XXII. 



wander about and select a suitable corner lor spinning up. As the 

 silk is spun in one single reelable thread, which is broken by the 

 emergence of the moth, those cocoons which are intended for silk 

 must be stilled (i.e., the enclosed insect must be killed) to prevent 

 their being spoilt in this way. Stifling is done by exposure to the 

 hot rays of the sun or by artificial heat. The cocoons which are 

 intended for silk are placed in water which is nearly boiling, one 

 end of the silk thread teased out and thrown on to a compound 

 thread from four or live other cocoons and the whole reeled on to a 



Fig. 91. -The Mulberry Silkworm (Bombyx mori.) I, Larva; 2, 3, Cocoons ; 

 t. Male Moth; 5. Female Moth. (After Indian Museum Notes.) 



spool, other cocoons being attached as one conies to an end. 

 1 hose COCOOns which are intended to be kept lor rearing purposes 

 an retained and the moths allowed to emerge, pair and oviposit in 

 due course. As the silkworms are very subject to numerous diseases 

 which arc transmitted hereditarily, each female moth is confined 

 over a sheet of paper under a tin funnel whilst laying her eggs; 

 when oviposition is concluded, the body-juices of the parent arc 

 examined microscopically to see whether disease is present and, if 

 so, that batch of eggs is destroyed. Scrupulous cleanliness in the 

 rearing-trays and proper disinfection of these trays and the chand- 

 rakhis are essential for success in rearing these, as in all other, 

 insects. 



The Eri Silkworm (Attacus ricini) feeds on the leaves of castor 

 and is normally an inhabitant of Assam and Bengal but has been 



