NOMENCLATURE OF THE APPENDAGES. 101 



6. Figure: In figure they may be linear, winged, 

 appendiculated, round, channelled, compressed, spines- 

 cent, and so on 



a. Linear when they are equal in breadth throughout, as in the 

 lemon-tree. 



b. Winged having their expansions on each side, as in the 

 orange-tree. 



c. Appendiculated when furnished with leaflets at its base, as 

 in the small teasel. 



d. Round round throughout, as in the garden pea. 



e. Channelled when it is dilated to its base, as in the wild 

 angelica. 



f. Compressed compressed towards its base, as in the trembling 

 poplar. 



g. Spinescent becoming a spine after the fall ef the leaf, as in 

 the purging buckthorn. 



8* Insertion: In insertion, the leaf-stalk is termed 

 inserted, articulated, adhering, decurrent, amplexicaul, 

 and vaginate. 



a. Inserted when it is attached, as in the common pear and 

 most trees. 



b. Articulated when it is in joints, as in the common wood-sorrel. 



c. Adhering adhering so to the stem, that it cannot be displaced 

 without injuring the bark. 



cl. Decurrent adhering at its base, and going some little way 

 down the stem, as in the black-seeded pea. 



e. Amplexicaul surrounding the stem at its base, as in the spleen- 

 wort-leaved groundsel, 



f. Vaginate surrounding or sheathing the stem with a perfect 

 tube, as in the common Indian shot. 



9. Composition : In composition, the petiole is either 

 simple or compound. 



a. Simple when not divided, as in most leaves. (F. 40, f.) 



b. Compound when divided into other leaf-stalks, as in all com- 

 pound leaves. (F. 36.) 



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