408 APPENDIX. 



ter in their silk reservoirs had become so congealed and tenacious 

 from cold, as to resemble strong tendons ; which sufficiently ac- 

 counted for the inability of the insect to draw forth the silken fila- 

 ment. Yet no sooner is the temperature increased, than they will 

 resume their labors with increased activity ; but will again desist, if 

 exposed again to cold. If neglected at this critical period, they as- 

 sume, in due time, the chrysalis form, but, for want of sufficient 

 strength, leave incomplete their silken tomb. 



CHAPTER III. VARIETIES OF SILK-WORMS. 



1. Sina Silk- Worm. This is a variety imported into France from 

 China,Tjy Lours XVI., in 1784 ; a large, pure white, and extremely 

 beautiful variety, which is preferred, in that country, to all others. 

 Their cocoons are pure white, large, and fine, and the silk-worms 

 hatch simultaneously. 



2. The Large Single-Crop Worm. A very superior variety, wheth- 

 er of a pure white or brown. Their period of hatching may be 

 hastened or prolonged to a late period in summer ; and thus they will 

 yield two crops or more. The cocoons, being of large size, are on 

 this account more profitable to raise or to reel, than any other varie- 

 ty except the Sina. 



3. The Silk- Worm of Two Crops. A small variety, from Italy ; a 

 pale, white worm; the silk is white, and very fine ; the cocoons are 

 also small, and, on this account, deemed unprofitable. 



4. Silk- Worm of Eight Crops, or Dacey. At the silk establishment 

 of the British East India Company at Jungepore, in Bengal, besides 

 the Common silk-worm, which produces but a single crop annually, 

 they have also another silk-worm, called Dacey, which produces 

 eight crops or harvests, and is supposed to be indigenous. 



5. Friuli Silk-Worms. There is a variety of silk- worms found in 

 Friuli, so very large, that two of these, when fully grown> will out- 

 weigh five of the common kind; and their cocoons weigh almost in 

 the same proportion. The quantity of food is one tenth" less in pro- 

 portion to the weight of cocoons produced, than the common kind, 

 but they require five or six days longer in their evolutions before 

 they begin to spin. Their cocoons are four times as heavy as those 

 of the small variety of silk-worm. Each cocoon yields nearly 8 

 grains, and measures almost 1.300 yards; and 100 cocoons weigh a 

 pound, and 1,091 will yield a pound of pure reeled silk. Friuli silk 

 is said to cause more trouble and waste in its manufacture, than that 

 of either France or Lombardy. This may be owing, either to the 

 breed of silk-worms, or, what is much more probable, to its being 

 imperfectly reeled. 



For an account of the two following kinds of silk-worms, which are 

 described as peculiar to Hindoostan, I am indebted to the researches 

 of General Dearborn, who has described them from Atilburn's Ori- 

 ental Commerce. 



6. Arrindy Silk-Worm. This silk- worm is a species totally differ- 

 ent from any hitherto described or known, and is called Arrindy, 

 from the name of the plant, the Rhicinus, or Palmi Christi, on which 



