FORM OB FIGURE. 



51 



orbicular in figure and larger than any other, presenting the form of the 

 ancient lyre, the form is termed lyrate. 



143 144 145 146 



Feather-veined leaves almost compound. 143, Nigella (pinnatisect). 144, Cheledonium ma- 

 jus. 145, Thistle (Cirsium lanceolatum). 14G, Dandelion (runcinate-lyrate). 



270. Pinnately parted implies that the incisions are deeper than 

 pinnatijid, nearly reaching the midvein. In either case the leaf is said 

 to be sinuate when the incisions (sinuses) as well as the segments are 

 .rounded and flowing in outline. Such segments are lobes, and the leaves 

 lobate or lobed, a very generic term. 



271. The palmate venation presents us with a set of forms which 

 are, in general, broader in proportion than the pinnate, having the 

 breadth about equaling the length. Such a leaf may be rarely broadly 

 ovate or broadly cordate, terms which require no further explanation. 

 Or it may be 



Beniform, kidney -shaped, having a flowing outline broader than long, 

 concave at base ; or 



Peltate, shield-form, the petiole not inserted at the margin but in the 

 midst of the lower surface of the blade. This singular form evidently 

 results from the blending of the base lobes of a deeply cordate leaf, as 

 soon in hydrocotyle. It may be orbicular, oval, etc. 



272. Palmate forms. The following result from deficiency of tis- 

 sue, causing deep divisions between the veins. Leaves thus dissected 

 are said to be palmately -lobed when either the segments or the sinuses 

 are somewhat rounded and continuous. The number of lobes is do- 

 noted by such terms as bilobate, trilobate, Jive-lobed, etc. ; 



