Animals that Set Traps 



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are spread between pebbles, or across crevices 

 in rocks, and serve as true gill-nets to capture 

 minute swimming creatures upon which caddis- 

 worms feed, but which they could not other- 

 wise catch in sufficient abundance. 



Another familiar and pertinent example is 

 that of the pit of the ant-lion, a true trap. 

 The larva of the tiger-beetle, whose widely 

 opened jaws fill the mouth of his burrow, is a 

 living trap, made to snap, precisely like a fur- 

 hunter's steel-trap, on the heedless insect that 

 steps into it. 



The jelly-fish as it sails gracefully through 

 the surface of the sea is another living trap 

 of the most deadly kind. There is floating about 

 him in all directions, and to a distance (in the 

 largest ones) of several feet, a perfect tangle 

 of extremely delicate ribbons, like the flying 

 hair of a Medusa head, which are as transparent 

 as glass and as deadly as poison to all small 

 swimmers. Let a minnow or shrimp or some one 

 of the hundreds of sorts of young creatures 

 that float in the ocean run against these unseen 

 threads, and they will cling to him, envelop him 



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