NATURAL HISTORY STUDIES 



tail of theirs is filled, which immediately, upon its 

 being exposed to the air, turns to a dry substance, 

 and exceedingly rarifies and extends itself." 



Dr. H. C. M'Cook, who has contributed so much 

 in a charming way to our knowledge of North 

 American spiders, gives a precise account of the 

 spider's position during the ballooning ; and it is 

 interesting to notice, as he points out, that here 

 again the gist of the matter was accurately observed 

 by Master Jonathan Edwards. " As the spiderling 

 vaults upward, by a swift motion the body is 

 turned back downward, the ray of floating threads 

 is separated from the spinnerets and grasped by the 

 feet, which also by deft and rapid movements weave 

 a tiny cradle or net of delicate lines, to which the 

 claws cling. At the same time a second silken 

 filament is ejected and floats out behind, leaving 

 the body of the little voyager balanced on its meshy 

 basket between that and the first filament, which 

 now streams up from the front. Thus our aeronaut's 

 balloon is complete, and she sits or hangs in the 

 middle of it, drifting whither the wind may carry 

 her." 



Dr. M'Cook makes a useful suggestion in regard 

 to the shreds and flakes often seen floating or sinking 

 down without any spiders about them. " In many, 

 perhaps in most, cases a number of feints are made 

 before ascent. A spider will take due position and 

 spin out a thread ; but it fails to mount aloft. 

 Other unsuccessful attempts follow, each producing 

 a filament. These, while waving to and fro in the 

 eddying air, are often tangled together before they 



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