LEAVES 



133 



these veins parallel ? Hold the leaf up towards the light and see 

 how the main veins are connected by smaller ueinlets. Examine 

 with your glass the leaf as held to the light 

 and make a careful sketch of portions of 

 one or two veins and the intersecting vein- 

 lets. How is the course of the veins shown 

 on the upper surface of the leaf ? 



Examine both surfaces of the leaf with 

 the glass and look for hairs distributed on 

 the surfaces. Describe the manner in which 

 the hairs are arranged. 



FIG. 94. Netted Vein- 

 ing (pinnate) in the 

 Leaf of the Foxglove. 



The various forms of leaves are 

 classed and described by botanists with 

 great minuteness, 1 not simply for the 

 study of leaves themselves, but also 

 because in classifying and describing 

 plants the characteristic forms of the 

 leaves of many kinds of plants form 

 a very simple 

 and ready 



means of distinguishing them 



from each other and identifying 



them. The student is not ex- 

 pected to learn the names of the 



several shapes of leaves as a 



whole or of their bases, tips, or 



margins, except in those cases 



in which he needs to use and 



apply them. 



Many of the words used to describe the shapes of leaves 



are equally applicable to the leaf-like parts of flowers. 



FIG. 95. jetted Veining (pal- 

 mate) in Leaf of Melon. 



See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 623-637. 



