THE HEDGE-BANK. 49 



nating in exquisitely fine points. Each of these 

 rises from a swoln base, which contains in it a drop 

 of fluid, so acrid, that when received into the circu- 

 lation it irritates and inflames the part affected, so 

 as to cause considerable inconvenience, which lasts 

 sometimes for several hours. The mechanism by 

 which this process is carried on is most wonderful, 

 and on this account the nettle is what I have stated 

 it to be, an object well-worthy of the examination 

 of the curious. Each little spike, though so slen- 

 der as to be no more than barely visible to the 

 naked eye, is a hollow tube performing a two-fold 

 office ; first, that of piercing the skin, and next, that 

 of conducting the poison from the swoln part of the 

 base into the flesh of the person who touches it ; 

 for what appears to be a point is in reality the 

 open end of the tube. The spike itself is rigid, 

 while the case of poison is soft, yielding to the 

 slightest pressure. When you touch the leaf with 

 your hand gently, the spike pierces the skin and 

 buries itself to the base, so that the surface of the 

 skin presses on the bag of poison, some of which 

 is forced up through the tube and conveyed into 

 the wound, where it instantly mixes with the 

 blood, and causes the sensation of stinging, which 

 you find so annoying. 



The construction of the sting in the bee and wasp 

 is precisely similar, the bag of poison being con- 

 cealed within the body of the insect, except when 

 it chooses to make use of its small but formidable 

 weapon, when it is placed in such a position as to 

 be pressed on by the surface which is wounded. 

 The dangerous fang of the viper, and the deadly 

 one of the rattle-snake, differ only in one respect : 

 being stouter than the stings of the bee and nettle, 



