LESSON 9.] 



filMl'LK AND C'OMPOLNU LKAVES. 



CI 



LESSON IX. 



MORPHOLOGY OF M'.AVKS AS I'OMAOK. SIMIMJ-: AND COM- 

 POUND m:avi:s, stipulks, etc. 



154. In the foregoing Lesson leaves have been treated of in their 

 simplest form, namely, as eonsisting of a single blade. But in many 

 cases the leaf is divided into a number of separate bhules. Tiiat is, 



155. Leaves arc cillier Simple or Compoimtl. They are srid to be 



simple, when the blade is all of one piece : they are compound, when 

 the blade consists of two or more separate pieces, borne upon a 

 common leaf-stalk. And between these two kinds every interme- 

 diate gradation is to be met with. This will appear as we proceed 

 to notice the j)rincipal 



1 50. Forms of Leaves as to particular Oiitliiic or degree of division. 



In this respect, leaves are said to be 



Entire, when their general outline is completely fdled out, so that 

 the margin is an even line, without any teeth or notches ; as in 

 Fig. 83, 84, 100, &c. 



Serrate, or saw-toothed, when the margin only is cut into sharp 

 teeth, like those of a saw, and jwinting forwards; as in Fig. 112: 

 also DO, &c. 



A>j,% 



Dentdtc, or toot/ird, when 

 of forwards; as in Fig. 113. 



such teeth point outwards, instead 



FIG. 11'J-1I7. KiiiJs uf martin i>no5 



6 



