190 DIRECT BEXEFITS DERIVED FROM INSECTS. 



same time cheap and durable dress, such as this silk furnishes, is much 

 wanted. The durability of this silk is indeed astonishing. After constant 

 use for nine or ten years it does not show an}' signs of decay. These 

 insects are thought by the natives of so much consequence, that they guard 

 them by day to preserve them from crows and other birds, and by night 

 from the bats. The Arindy silk-worm (^Saturnia Cynthia Drury), which 

 feeds solely on the leaves of the Palma 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 Hke cotton ; and the thread thus 

 manufactured is woven into a coarse kind of white cloth of a loose texture, 

 but of still more incredible durability 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. A moth allied 

 to this last species, but distinct, has been described and figured by Colonel 

 Sykes, who met with its leather-like cocoons composed of silk so strong, 

 that a single filament supported a weight of 198 grains, in that part of the 

 Deccan in India lying between the sources and junction of the Bema and 

 Mota Mala rivers. These cocoons are called kolesurra by the Mahrattas, 

 who use them cut into thongs, which are more durable than leather for 

 binding the matchlock barrel to the stock ; but as far as Colonel Sykes 

 could ascertain, no use is made of the silk in Western India, though there 

 can be little doubt that it might be advantageously produced, as the cater- 

 pillars which spin it feed indiscriminately on the Teak tree {Tectona grandis), 

 the Mulberry (Morus indica), the Bor {Zizyphus Jujuba), and the Osana 

 ( Terminalia alata glabra) } 



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

 Young's Annak of Agriculture^, are known in China, and have been intro- 

 duced into Inilia. " 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 breeding of the larvse 

 of any European moths, as Calocala pacta, sjwnsa, &c. proposed with this 

 view by Fabricius*, 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 deceive me) upon the Euonj/mun, and from the twigs 

 of which (not the cocoon) I unwound it. It is even asserted that in 

 Germany a manufacture of silk from the cocoons of the emperor moth 

 (Saturnia Pavonia major) was at one time established.* There seems no 

 question, however, that silk might be advantageously derived from many 

 native silk-worms in America. An account is given in the Philosophical 

 Transactions of one found there, whose cocoon is not only heavier and 

 more productive of silk than that of the common kind, but is so much 



1 Trans. Royal Asiat. Sac. 1834. vol. ill. 2 xxiii. 235. 



' Vorlesungen, 325. * Latr. Hist. Nat. xiv. 150. 



