DIRECT BENEFITS DERIVED FROM INSECTS* 333 



Drury), which feeds solely on the leaves of the Palrna 

 Christi, produces remarkably soft cocoons, the silk of 

 which is so delicate and flossy, that it is impracticable to 

 wind it off: it is therefore spun like cotton ; and the thread 

 thus manufactured is woven into a coarse kind of white 

 cloth of a loose texture, but of still more incredible dura- 

 bility than the last, the life of one person being seldom 

 sufficient to wear out a garment made of it. It is used 

 not only for clothing, but for packing fine cloths, &c. 

 Some manufacturers in England to whom the silk was 

 shown, seemed to think that it could be made here into 

 shawls equal to any received from India. 



Other species, as may be inferred from an extract of a 

 letter given in Young's Annals, of Agriculture*, are known 

 in China, and have been recently introduced into India. 

 " We have obtained, " says the writer, " a monthly silk- 

 worm from China, which I have reared with my own 

 hands, and in twenty-five days have had the cocoons in 

 my basins, and by the twenty-ninth or thirty-first day a 

 new progeny feeding in my trays. This makes it a mine 

 to whoever would undertake the cultivation of it." 



Whether it will ever be expedient to attempt the breed- 

 ing of the larvae of any European moths, as Noctua pacta, 

 Sponsa, &c. proposed with this view by Fabricius 5 , seems 

 doubtful, though certainly many of them afford a very 

 strong silk, and might be readily propagated ; and I have 

 now in my possession some thread more like cotton than 

 silk spun by the larva of a moth, which when I was a very 

 young entomologist I observed (if my memory does not 



A xxiii. 235. b Vorlesungen, 325. 



