22 



A STUDY OF LEAVES. 



SURFACE. 



Hairs are a leaf's weapons of defense. The 

 microscope reveals their varied forms. 



Hairs of plants much magnified. 



Glands are cells at the base of hairs containing 

 watery liquid or oil. Sometimes the gland contains 

 a poisonous liquid and sends it through the hairs, 

 forming a sting like that of the Nettle. 



The following terms are applied : 



Glabrous — Smooth, without hairs 

 Tomentose — Woolly, with dense hairs. 

 Silky, soft — With dense, soft hairs. 

 Pruinous — Covered with blue powder. 

 Punctate— Dotted with glands. 



