BO 1 'A NIC A L TERMS. 



With RUxners : when there are slender branches from the 

 base of the stem which take root at the end, as in Straw- 

 berry, etc. (Fig. 11). 



With Stoloxs : when branches bend over so as to reach the 

 ground and take root (Fig. 11). 



With Si'CKErs : when an underground branch sends up a 

 stem at a distance from the parent plant, as in Mint, etc. 

 (Fig. 11). 



Tendrils are sometimes branch-forms, as those of the Grape 



(Fig. 12). 



Spines, as in Hawthorn, are also branch-forms, stunted and 

 pointed (Fig. 24), 



THE LEAF. 

 Parts. 



Blade : the broad part. 

 Petiole : the leaf-stalk. 



Stipules : tAvo small usually leaf-like pieces, one on each side 

 of the petiole where it joins the stem of the plant (Fig. 

 25) ; but sometimes the stipules are in the form of spines, 

 as in Locust, and sometimes they form a tube around the 

 stem, as in Smartweed (Fig. 27). 



Sheath : the tubular petiole which surrounds the stem in 

 many Eudogens (Fig. 26). 



LiGULE : the thin semi-transparent appendage growing at the 

 top of the sheath in most grassers. It appears to be an 

 upward extension of the lining of the sheath (Fig. 26). 



Position. 



Kadical : when arising from the stem at or below the surface 



of the ground. 

 Cauline : all the leaves higher up the stem. 



In plants like Dandelion and Hepatica all the leaves 



are radical. In Buttercup and Shepherd's Purse there 



are both kinds (Fig. 28). 



Arrangement. 



Alternate : when only one leaf springs from a node, or joint 

 of the stem (Fig. 29). 



Opposite : when two leaves spring from each node on oppo- 

 site sides of the stem ; and opposite leaves are decussate 

 when each pair is at right angles to the next pair 

 (Fig. 30). 



Whorled, or Yerticillate : when three or more leaves 

 spring from a node (Fig. 31 1. 



Fasciculate : when there are several leaves in a bundle, as 

 in Pine, Larch, etc. (Fig. 32). 



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