THE GARDEN SPIDER. 177 



The best known of these creatures is the common Garden 

 Spider {Epeira diadcma), sometimes called the Geometric 

 Spider, whose beautifully radiated net is so familiar that its 

 general shape requires no description. Suffice it to say, that 

 the spider exhibits wonderful skill in placing its web, making a 

 framework of very strong threads or ropes, and then spinning 

 the net itself between them. Very great strength is thus ob- 

 tained, for the threads are exceedingly elastic ; so that, al- 

 though stretched tolerably tightly, they will yield to pressure, 

 and immediately recover themselves. This property is very 

 needful, in order to enable them to resist the wind, to which 

 they are so fully exposed. 



These spiders have, moreover, a most singular plan of 

 strengthening their web, when the wind is more than or- 

 dinarily violent. If they find that the wind stretches their 

 nets to a dangerous extent, they hang pieces of wood, or stone, 

 or other substances to the web, so as to obtain the needful 

 steadiness. I have seen a piece of wood which had been thus 

 used by a Garden Spider, and which was some two inches in 

 length and thicker than an ordinary drawing-pencil. The 

 spider hauled it to a height of nearly five feet ; and when by 

 some accident the suspending thread was broken, the little 

 creature immediately lowered itself to the ground, attached a 

 fresh thread, ascended again to the web, and hauled the piece 

 ot wood after it. 



It found this balance-weight at some distance from the web, 

 and certainly must have dragged it for a distance of five feet 

 along the ground before reaching the spot below the web. 

 There were eight or ten similar webs in the same verandah, 

 but only in the single instance was the net steadied by a 

 weight. 



The structure of the beautiful web is very remarkable. 



It is nearly circular, and is composed of a number of straight 

 lines, radiating from a common centre, and having a spiral line 

 wound regularly upon them. Now, the structure of the ra- 

 diating and the spiral lines is quite distinct, as may be seen by 

 applying a microscope of moderate power. The radiating 



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