POISONOUS PLANTS AND ANIMALS 



is a little animal known as the harvest-man. These are 

 the young of a small red spider-like creature, called 

 Trombidium. They get on to the feet of persons walk- 

 ing in the grass, and crawl up the legs and burrow into 

 the tender skin. Benzine will keep them away if applied 

 to the ankles or stockings when they are about, and will 

 also destroy them once they have effected a lodgment. 



FIG. 15 bis. A. Highly magnified draw- 

 ing of a stinging hair of the common 

 nettle. The hair is seen to be a single 

 cell or capsule of large size, taper- 

 ing to its extremity, but ending in a 

 little knob. The hard case e is filled 

 with liquid a, and is lined with slimy 

 granular " protoplasm " b, which ex- 

 tends in threads across the cavity to the 

 " nucleus " c. The ordinary small cells 

 of the nettle leaf are marked d. B shows 

 the knobbed end of the stinging hair, 

 and the way in which, owing to the 

 thinness of its walls, it breaks off along 

 the line xy when pressed, leaving a sharp 

 projecting edge, which penetrates the 

 skin of an animal, whilst the protoplasm 

 p, distended with poisonous liquid, is 

 shown in C, issuing from the broken 

 end. It would escape in this way when 

 the sharp, freshly broken end had pene- 

 trated some animal's skin. 



b. 



