OBOSS ANATOMY OIT FLOWERING PLANTS, xvii 



pinnately compound, Fig. XIII). Leaf-branches may branch again ; 

 thus we may have twice palmately hied and twice palmately com- 

 pound leaves, and likewise twice pinnately hied, twice pinnately 

 compound leaves, etc. etc. 



Fio. XII. Fia. xm. 



Fio. Xn.— Eadiately or palmately compound leaf. 

 Fio. XIII.— Pinnately compound leaf. 



Forms of Bladei — The forms of the blade may be concisely ar- 

 ranged as follows (Fig. XIV) : 



1. Bound (orbicular), with a circular outline, or nearly so. 



3. Ovate, which is longer than broad, and has a broader base 

 and a narrower apex (thereverse of this is the olovate). When the 

 base is divided into two rounded lobes the leaf is heart-shaped. 

 Related to the ovate is the rhomlic leaf with more or less angled 

 sides. The triangular leaf is another modification in which the base 

 is truncate (cut off). The very short and broad modification of the 

 heart-shaped blade is the hidney-shaped leaf (reniform). The nar- 

 row ovate is the lanceolate form, while its reverse is the ollanceo- 

 late (spatulate). 



3. elliptical, which is longer than broad, has base and apex 

 equal, and sides rounded. 



4. Olhng, which is two to three times longer than broad, with 

 straight, parallel sides. Varieties of this are the linear, which 

 is very narrow and long: when this is rigid and sharp at the apex 



