39 [ 175 3 



shelves when at their full growth, will fill only a small part; the first 

 two weeks, therefore, where the object is to keep the shelves con- 

 stantly filled with the greatest possible quantity of worms, something 

 may be gained by having each crop hatched out on several different 

 days, and each day's hatching kept by itself. Under this management, 

 the hatching may be so arranged as to keep the shelves filled with 

 worms of different ages, and of all sizes, which will enable the shelves 

 to hold twice as many worms as they would otherwise admit of; and 

 this management will also give the tenders constant and regular em- 

 ployment; every few days they will have some new cocoons of silk to 

 remove from the shelves, and some young worms to put on to supply 

 their places." 



Remarks. — In the warm States, which abound with many unem- 

 ployed hands, the foregoing plan may be put in execution. But the 

 trouble attending it will probably cause few, if any, to attempt it. 

 Confusion and injury would moreover ensue, from having young 

 worms on the same shelves with the worms spinning their cocoons, (a 

 time when they require to be kept perfectly quiet,) even were it prac- 

 ticable to accommodate both. Mr. M. has, however, demonstrated, 

 that more than two crops of worms can be raised in those States where 

 the heat continues long and steady. 



" Messrs. Weiss and Youngman, of Bethlehem, Pennsylvania, 

 raised two crops during the year 1825. The worms of the second 

 crop appeared more vigorous and healthy than those of the first. 

 They also produced larger cocoons, the silk of which was of a better 

 quality. ''* 



Two attempts, viz: in 1826 and 1827, to rear two crops of worms, 

 by Messrs, Terhoeven, Philadelphia county, failed. The worms, from 

 the eggs laid ifl the early part of the season, hatched, but they soon died. 



CHAPTER IIL 



OP OTHER CATERPILLARS PRODUCING SILK. 



The larva of the silk-moth is not the only insect which yields silk. 

 Other insects produce the same substance, which, in point of strength, 

 far exceeds that of the common silkworm. These insects are natives 

 of India, and bear the names of Bughy or Tusseh,t and ArrindyJ 

 silkworms, and have been fully described, and figured in colors, .by 

 the late eminent naturalist. Dr. Roxburgh. || Both exceed the common 

 vsilkworm in size ; the fir§t especially; and the silk of which appears 

 to be more valuable than that of the other kind. The Tusseh silk is 



* Dr. Stout: letter to the Hon. C. Miner, of the House of Representatives. 



■J" Phalzena Attaciis Paphia, of Drury. 



\ Bombyx Cynthia. 



!) Trans. Linna:3n Soc. Lond. vol. T. 



