PLANT ORGANS AND ORGANISMS 



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When a sessile leaf surrounds the stem more or less at the base, 

 it is called clasping or amplexicaul. Example: Poppy (Papaver 

 somniferum) . 



When the bases of two opposite leaves are so united as to form 

 one piece, they are called connate-perfoliate, as Eupatorium perfolia- 

 tum or Boneset. 



Leaves are called equitant when they are all radical and succes- 

 sively folded on each other toward their bases, as in Iris sp. 



The Forms of Leaves. Simple leaves are those having a single 

 blade, either sessile or petiolate. 



Compound leaves are divided into two or more distinct subdivi- 

 sions called leaflets, which may be either sessile or petiolate. 



Simple leaves and the separate blades of compound leaves are de- 

 scribed as to general outline, apex, base, marginal indentations, sur- 

 face and texture. 



(a) General Outline (form viewed as a whole without regard to 

 indentations of margin). Dependent upon kind of venation. 



When the lower veins are longer and larger than the others, the 

 leaf is Ovate, or Egg-shaped. Parallel-veined leaves are usually 

 linear, long and narrow of nearly equal breadth throughout 

 (Linaria), or lanceolate, like the linear with the exception that the 

 broadest part is a little below the center. Example: Long 

 Buchu. 



Elliptical, somewhat longer than wide, with rounded ends and 

 sides. Example: Leaf of Pear. 



Oblong, when longer than broad, margins parallel. Example: 

 Matico. 



Inequilateral, margin longer on one side than the other, as the 

 Hamamelis, Elm and Linden. 



Orbicular, circular in shape. Example: Nasturtium. 



Peltate, or shield-shaped, having the petiole inserted at the center 

 of the lower surface of the lamina. Example: Podophyllum. 



Filiform, or thread-like, very long and narrow, as Asparagus leaves. 



Ovate, broadly elliptical. Example: Boldo. Obovate, reversely 

 ovate. Examples: Short Buchu and Menyanthes. 



Oblanceolate, reversely lanceolate. Example: Chimaphila. 



Cuneate, shaped like a wedge with the point backward. 



