FROM THE ATTACKS OF ANIMALS. 143 



the cells of the epidermis, consists of stiff hairs, or 

 bristles, with thick, siliceous cell-walls, and sharp 

 points. They arise generally in great numbers on 



FIG. 39. WEAPONS OF PLANTS. 



3. Section through a Leaf of Nettle (Urtica dioica), provided with Stinging Hairs. 6. Bristle 

 of the Bugloss (Echium Italicum). 7. Margin of the Scabrous Leaf of a Sedge (Carex 

 stricta). 8. Margin, beset with Barbs, of a Leaf of a Scabrous Grass (Festuca arundi- 

 nacea). (" Pflanzenleben.") 



the upper surface of the green leaves, and turn 

 their points towards the side from which an attack 

 is to be expected. In comparison with the barbs 



