464. Mr. F. Pollock on the Epeira Aurelia. 



sight. I have seen a large insect almost touching a spicier in 

 in its web, but terrified and motionless; and as long as it re- 

 mained thus, the spider did not take the least notice of it, not 

 knowing apparently that it was there; directly, however, it 

 began to move, it was attacked and rolled up. 



I have said that the young spiders are very migratory. After 

 a change or two of skin they are equally stationary, and will, I 

 believe, if they find a suitable place, never move more than a 

 foot or two from it during their life, making web after web, and 

 cocoon after cocoon, in almost identically the same spot. 



They appear to be quite harmless to man, as I have frequently 

 handled the largest with perfect impunity. 



Their voracity, which is very great, is only equalled by their 

 powers of endurance ; for they will live for a week or ten days 

 without food, and apparently without being much the worse for 

 it. One male spider, which I had in a glass case, remained for 

 forty-eight days, after its final change, without eating ; and when 

 I let him go, he was quite brisk and lively. I may also mention 

 that when it was necessary that an adult spider should be 

 weighed (in order to find the rate at which they grow), think- 

 ing that the quickest and easiest manner of ending its life 

 would be to put it into hot water, a jug was brought, the spider 

 dropped in, and it apparently died at once ; so, taking it out of 

 the hot water, I dried it thoroughly, and put it into the scales. 

 To my utter surprise, it began, after a while, to show signs of 

 returning life. When sufficiently recovered, I placed it carefully 

 back into its web, and from that time forth it was just as healthy 

 a spider as any untouched one^ perhaps all the better for its 

 cleaning and its bath. 



I found that at the end of eight months it is 3700 times as 

 heavy as at its birth ! 



The nutriment it takes during the first half of its life is de- 

 voted entirely to increasing its size; that of the last half almost 

 as entirely to the production of eggs. 



We have seen that it has altogether ten changes of skin — one 

 in the cocoon, and nine out of it ; and that it makes ten cocoons, 

 and lays about 8000 eggs. 



So regular are the habits of this spider, that it may be 

 likened to a machine which is made for performing a given 

 amount of work and no more. If it can procure an abundance 

 of food, it will live for about eighteen months ; and it may ap- 

 pear somewhat anomalous, but nevertheless I believe it to be a 

 fact, that by lengthening out the time in which it gets its food 

 you may considerably prolong its existence, though you cannot 

 get more work out of it, either in the shape of growth, or 

 changes of skin, or laying eggs. 



