400 HOUSEHOLD INSECTS 



venom into the wounds made when it bites a victim. 

 This may account, in part, at least, for some of the 

 variations in the results of different spider-bites. The 

 venom, says Castellani and Chalmers, "is an oily, trans- 

 lucent, lemon-yellow-coloured liquid with an acid reaction 

 and a hot bitter taste." 



The venom of spiders is undoubtedly of sufficient 

 virulence to kill certain insects ; although Blackwall 

 came to the conclusion from his experiments that the 

 deaths of spider-bitten insects resulted from the loss of 

 blood rather than from the effects of poison. He found 

 that bees, wasps, and grasshoppers survived the bites 

 of spiders about as long as they did the effect of needle- 

 pricks inflicted in the same parts of the body. Other 

 experimenters have found that the bites of spiders 

 are fatal to insects, probably due to the effect of the poison. 

 The amount of poison necessary to paralyze or kill an 

 insect, however, w r ould not necessarily have much effect 

 upon so large a body as that of a human being. There is 

 much conflicting evidence regarding the whole matter. 



Blackwall allowed spiders to bite him and could not 

 distinguish the sensation from that of a needle-prick made 

 upon the hand at the same time. On the other hand, 

 Bertkau, when bitten, felt clearly the effects of an irritant 

 poison in the wound, but suffered no serious consequences. 



Baron Walckenaer tested the effect of spider-bites on 

 his own person. He allowed himself to be bitten by some 

 of the largest species of spiders found in the vicinity of 

 Paris. With him the sensation from the punctures pro- 

 duced by the fangs was not unlike that produced by the 

 prick of a fine needle. Moreover, there were no subse- 

 quent harmful effects. In his opinion, the venom of a 



