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themselves, and lie in ambush for their prey. 

 Between this cell and the principal web they 

 extend a thread of communication, and by the 

 vibrations into which this thread is thrown, on 

 the contact of any solid body, the spider is im- 

 mediately acquainted with the event, and passes 

 quickly to the spot, by the assistance of the 

 same thread. 



Some species have the power of conveying 

 themselves to considerable distances through the 

 air by means of threads which they dart out, 

 and which are borne onwards by the wind, 

 Avhile the spider is clinging to the end of the 

 thread which is next to it. In this manner these 

 spiders are often carried up to a great height in 

 the air : and it has been supposed that during 

 their flight they often seize upon gnats and other 

 flies ; because the mutilated remains of these 

 insects are often seen adhering to the threads : 

 this point, however, is still open to much 

 doubt. 



The Natural History of the spider is in many 

 points of view highly interesting, not only from 

 the great extent to which the organic develope- 

 ment is carried, and the energy with which all 

 the functions of animal life are performed ; but 

 also with reference to the wonderful instincts 

 displayed in the construction of its web, in the 

 surprise and destruction of its victims, and in 

 the zealous guardianship of its young. It would 



