78 THE VEGETABLE WORLD. . 
There is not less diversity in their length and breadth, than in 
their form. While some leaves are only half a line in length, 
Fig. 95.—Ranunculus aquatilis. 
others attain the dimensions of five or six yards. Nor is their size 
always proportioned to the thickness of the stem which carries 
them. The leaves of a small plant, the 
Dock-leaf (Ruwmex), would cover many — 
hundred times the space occupied by the 
fascicled leaves of the Larch, an imposing 
mountain tree; and there is a thousand 
times less vegetable matter in the leaf of 
the Fir-tree or Cedar than in that of the 
Plantain, or Banana-tree. 
The leaf usually consists of two parts—@ 
stalk, or petiole, and the blade, or lamina. 
The petiole connects the leaf with the branch 
Fig. 96. Paemage toe gaa ofthe or stem, and is composed of a bundle of besa 
expanded fibres covered by an_ epidermls- 
When the petiole fails, as in the common Flax (Linum), Fig. 96, 
the leaf is said to be sessile. In such cases the leaves often partially 
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