THE TRIANGLE SPIDER. 



651 



equaled by her capacity for action when the moment arrives ; and 

 yet she is by no means hasty ; as a general thing (the exceptions 

 being due perhaps to hunger, or inexperience), the vibration of the 

 net by an insect must be pretty decided, and at least once repeated, 

 before the spider feels justified in springing her trap ; and when, as 

 may sometimes happen naturally, but more often through experiment, 

 a large or fierce insect is put into the net, nothing will induce the 

 spider to budge ; she will suffer her net to be wholly destroyed rather 

 than expose herself or her reputation (?) to a doubtful encounter. 

 Let us suppose, howevei\ that a common fly, or a gnat, or a moth, has 



Yio. 9. Net of the Triangle Spider 



WHEN LET GO FOR THE ENTANGLEMENT 



op Prey. The base-line is more near- 

 ly straight, and the apex-line is taut, 

 the slack having disappeared. 



struck the net in passing it may have touched a single double line 

 but this adheres with the greatest tenacity, and is so elastic as to 

 yield without breaking, so that each struggle involves the victim still 

 more, and may even bring it into contact with the next interradial. 

 As soon as the violence and repetition of the vibration indicate that 

 an insect is really entangled, the spider awakes from her apparent 

 apathy ;, she lets go with her hinder feet; the net, released from its 

 tension,. flies forward, and at the same time flaps from side to side. 



The comparative inertia of the fly causes the two or three double 

 lines next to it on the side toward the apex to be, as it were, propelled 

 against it, and the entanglement is aided by the sidewise flapping 

 already mentioned ; as may be imagined, all this is pretty apt to in- 

 volve the fly beyond the possibility of escape ; but, if the spider does 

 not feel certain of this, she creeps backward again, foot over foot, as 



