THEIR FORM, DIVISION, ETC. 



169 



dril (Fig. 216). It is impari-pinnate, or pinnate with an odd leaf- 

 let, when the petiole is terminated with a leaflet (Fig. 215, 220). 

 There are some subordinate modifications ; such as lyrately pin- 

 nate, when the blade of a lyrate leaf (Fig. 212) is completely di- 

 vided, as in Fig. 220 ; and interruptedly pinnate, when some mi- 

 nute leaflets are irregularly intermixed with larger ones, as is also 

 shown to some extent in the figure last cited. The number of 

 leaflets varies from a great number to very few. When reduced to 

 a small number, such a leaf is said to be pinnately seven-, jive-, or 

 tri-foliolate, as the case may be. A pinnate leaf of three or five 

 leaflets is often called ternate, or quinate ; which terms, however, 

 are equally applied to a palmately compound leaf, and also, and 

 more appropriately, to the case of three or five simple leaves 

 growing on the same node. A pinnately trifoliolate leaf (Fig. 

 221) is readily distinguished by having the two lateral leaflets 



212 



attached to the petiole at some distance below its apex, and by the 

 joint which is observable at some point between their insertion and 

 the lamina of the terminal leaflet. Such a leaf may even be re- 

 duced to the paradoxical case of a single leaflet ; as in the Orange 

 (Fig. 218), and frequently in one variety of Rhynchosia tomen- 



FIG. 211 - 221. Compound and lobed leaves. 



15 



