The Hunting Wasps 



more or less distant from one another; some- 

 times, but rarely, they are close together. 

 Altogether they possess a certain inde- 

 pendence of action, so that an injury done 

 to any one of them induces, at any 

 rate for the moment, the paralysis only 

 of the limbs that correspond with it, with- 

 out affecting the other ganglia and the 

 limbs which they control. To strike in 

 succession these three motor centres, each 

 farther back than the one before it, and to do 

 so between the first and second pair of legs 

 seems an impracticable operation for such a 

 weapon as the Wasp's sting, which is too 

 short and is besides very difficult to guide 

 under such conditions. It is true that certain 

 Beetles have the three ganglia of the thorax 

 very near together, almost touching, while 

 others have the last tv/o completely united, 

 soldered, welded together. It is also a 

 recognized fact that, in proportion as the dif- 

 ferent nervous nuclei tend towards a closer 

 combination and greater centralization, the 

 characteristic functions of animal nature be- 

 come more perfect and consequently, alas, 

 more vulnerable. Here we have the prey 

 which the Cerceris really needs. Those 

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