INSTINCT AND INTELLIGENCE 



The particular method of attack and capture prac- 

 ticed by each species in securing its prey is instinctive. 

 Ammophila pricks a number of gan- 

 glia along the ventral face of the 

 caterpillar; Pelopaeus, we believe, 

 stabs the spider in the cephalo- 

 thorax, and probably the several 

 species of Pompilus do the same. 

 Astata bicolor adopts the same tac- 

 tics in capturing her bugs, while it 

 is said of the flycatchers that they 

 commonly overcome their victims 

 without using the sting. It is by in- 

 stinct, too, that these wasps take 

 their proper food supply, one 

 worms, another spiders, a third 

 flies, moths, or beetles. So strong 

 and deeply seated is the preference, 

 that no fly robber ever takes spiders, nor will the ravisher 

 of the spiders change to beetles or bugs. 



The mode of carrying their booty is a true instinct. 

 Pompilus takes hold of her spider anywhere, but always 

 drags it over the ground, walking backward; Oxybelus 

 clasps her fly with the hind legs, while Bembex uses the 

 second pair to hold hers tightly against the under side 

 295 



PARALYZED SPIDER HUNG 

 UP ON SORREL BY QUIN- 

 QUENOTATUS WHILE SHE 

 DIGS HER NEST 



