5154 Entomolog ica I Society, 



less than five minutes, (it had been starved several times) : it required some time to 

 teach them to take the living flies that I presented to them on the end of a cleft stick, 

 and to acquire the dexterity of disengaging them without breaking: when at liberty 

 they rush upon the flies caught in their nets, and if they are eatable they carry them 

 to one part of their web where they unite together in enlacing them with their threads. 

 I have made some experiments upon the limit of fasting among these creatures, in 

 order to see if I might hope to transmit them alive to France. Contrary to my ex- 

 pectation, and to the habits of hunting animals, the spiders experimented upon were 

 unable to seize a fly after the fourth day : one of them was put upon the balcony of 

 the house I live in, but its weakness was so great that it could no longer use its feet ; 

 thus I left it, hanging by one of its hinder feet: I do not know if it found upon its 

 thread a prey more appropriate to its feeble state than flies, but it recovered and spun 

 its web at the place in which I had put it. I followed with interest the fabrication of 

 this web ; I saw that at first the silk was more viscid, dried less readily, was conse- 

 quently more liable to be soiled, and was lighter coloured than the silk spun at a later 

 period. I studied their movements in order to endeavour to discover in the secret of 

 the web the means of winding off the thread : the large size of the silk, and a ray of 

 the sun, permitted me to follow at a distance this interesting work, but the spider 

 became lost to view when it passed behind the pillars of the balcony, and these inter- 

 ruptions overcame my patience. I learned, however, that it always rests on the same 

 side of the web, and that the latter is composed of two parallel cables formed of several 

 threads (eight or ten), not adhering to each other: these cables serve as a support to a 

 light net-work, as in the web of our river spiders. I remarked that in its work the 

 spider uses its hinder feet in the same manner that the thread-maker and spinner use 

 their fingers; it draws them alternately over the thread which it makes, in order to 

 give it regularity, whilst its fore feet serve to move its body upon the threads already 

 dry. The cocoon was made in a very few days in the month of August: looking at it 

 in the month of January I found two very little spiders, which had very large bodies, 

 and very short and slender feet. I think that it would not be difficult to transport 

 these spiders in such condition that it would be possible to wind off their silk ; but 

 even when this result could not be attained absolutely, or within such limits of cost 

 as industrial application admits, it is probable that commerce could use profitably a 

 substance so resistant as this silk, spun like waste silk, and to obtain which all the 

 labour required at the places of its production consists in a simple gathering unat- 

 tended with danger. Industry, maritime especially, requires a thread which has the 

 qualities of silk, great tenacity withrin a small compass, less alterable by atmospheric 

 agencies and humidity than vegetable cords, and of which the price would not exceed 

 the requirements of its utility. The spider's silk can be used to supply this want, in- 

 asmuch as all hot countries would very soon furnish an important quantity of the rough 

 produce for the requirements of this new industry. We should remember, in this ex- 

 pectation, the predilection of the spider for inhabited places, and its harrnlessuess to the 

 trees where it establishes itself. Besides, its enemies, the musquitoes and flies, are also 

 ours, and it is in order to free us from them that it loves to be in our neighbourhood, 

 which is shunned by other animals in a state of nature. This consideration is not so tri- 

 fling as might be thought : the spiders distributed among the ornamental trees that sur- 

 round habitations would do much to abate this nuisance in hot and moist countries. 

 M. Margain put a spider upon a young Baobab in his court-yard, and he could tell you 

 the result of this experiment. The silk of the cocoon, by its durability and the bright- 



