PARALYZE]) IMIOVENDER 437 



In order to understand what has just taken place, let 

 us examine the victim's anatomy and structure. In outward 

 form spiders are diA'idcd into two distinct parts — the cephal- 

 othorax and the ahdomen. We are concerned chiefly with 

 the former, which is the first division of the creature, the 

 head and thorax, as it were, combined in one. The central 

 nervous system of the si)i(ler is, for the most part, concen- 

 trated in a mass of ^an^lions, clustered about the oesophagus. 

 The oesophagus is a tube throuoh which food passes from the 

 mouth to the stomach. It lies in the central portion of the 

 cephalothorax. That part of the central system lying above 

 is the brain, from which the optic nerves and those of the 

 biting and poisoning appendages arise. Lying below the 

 oesophagus is the ganglion from which the nerves of the legs 

 and palpi emerge. 



Now, sti'ange as it may seem, the wasp knows the above 

 paragraph by heart. She was an anatomist long before man. 

 She understood spiders long before man understood himself. 

 Her teacher was instinct, an immortal master. Thus in sting- 

 ing her spider she is like the master surgeon. With a single 

 tiny wound above, with a single lance below, she accomplish- 

 es the desired end. Into the spider's nervous center instinct 

 guides the wasp's poisoned dart. With precise strokes she 

 reaches the ganglions of her victim and spills her venom. 

 Henceforth no external outrage, however great, may be 

 transmitted to the brain; no volition in return will command 

 the forces of protest and defence. Like a party on a broken 

 wire, the spider lies helpless with tlie central office paralyzed ! 



In preparing pi'ovender for the cells, the methods em- 

 ployed by the majority of solitary wasps are more or less the 

 same. Yet the sting-poisons of different species produce 

 tw^o widely different effects on the victims. Both are doubt- 

 less forms of the same affliction; one, the commonest type, 

 acts instantly as I have just described. It causes complete 

 paralysis tliroughout the muscles that control walking, ])it- 

 ing, excretion and all exterior movements of the cephalo- 



