66 THE SILK WORM. 



throve, and went through all their mutations as satis- 

 fatory as if fed with their natural nourishment ; scarce- 

 ly any among them died, and the number and quali- 

 ty of the cocoons that were gathered, proved the en- 

 tire success of the experiment. If a solitary trial be 

 sufficient to establish a fact, this must certainly be 

 satisfactory to those who consider it desirable to nat- 

 uralize Silk Worms in this country, where, owing to 

 the inequality of seasons, the appearance of Mulberry 

 leaves must always be uncertain in regard to time. 

 Lettuce leaves have an advantage over other vegeta- 

 bles which have been offered as substitutes for the 

 Mulberry, that they may be gathered in wet weather 

 without themselves being wetted, as a lettuce, once 

 cabbaged, resists the entrance of all moisture within ; 

 and the heart being always perfectly dry, insures 

 nourishment to the Worm, free from that moisture 

 which is always found to affect it injuriously. 



" Mrs. Williams, an earlier correspondent of the 

 Society whose "Transactions" have been quoted, 

 give&a very minute and copious account of the vari- 

 ous trials which she made, of vegetable substances as 

 substitutes for Mulberry leaves. Having hatched her 

 brood in severely cold weather, when even lettuces 

 were not easily procurable, she offered to her Worms 

 the tender parts of blackberry leaves and relates that 

 the Worms ate them greedily. She next presented 

 to them young leaves of the elm, and reports that 

 equal success attended this trial ; encouraged by 

 these facts, she then succeeded in causing the insects. 

 to feed on the leaves and flowers of the sweet cow- 

 slip and primrose. But meanwhile thft Mulberry had 

 put forth its leaves, and having procured some of these 

 for her brood, it was thenceforth vain to offer them 



