CIRCUMSCRIPTION OF LEAVES. 423 



VII. Stipes*, is used to express the base or trunk of a from, 

 and is applied only to the Palms... Filices... and Fungi. 



CHAP V. 



OF SIMPLE LEAVES. 



LEAVES are to be considered in three respects, viz. as Sim- 

 ple. ..2. Compound. ..3. Determinate. We shall in this chap- 

 ter treat only of the simple. 



Simple leaves are such as have only a single leaf on a peti- 

 ole. They differ in respect to circumscription... angles... sinus,. » 

 apices.. .margin... superficies... /and substance. 



I. Circumscription considers the form of the circumference 

 of leaves where there are no angles or sinuations ; in which re- 

 spect leaves are, 



1. Orbiculate, round; when the longitudinal and transverse 

 diameters are equal, and the circumference circular. 



2. Subrotund, roundish; when the figure is nearly orbiculate, 



3. Ovate, egg-shaped; when the longitudinal diameter exceeds 

 the transverse, and the base is circumscribed with the segment 

 of a circle, but the apex is narrower. 



4. Oval, or eliptic; when the longitudinal diameter exceeds 



* The word in its proper signification means a trunk or stock of any plant : but 

 the sense in which the term is received in botany is as here explained : it is used 

 also to express the thread or fine trunk that supports the pappus in downy seeds. 

 See Pan h Chap. VII. Author. 



