128 LEAVES. 



trilobate or three-lobed, trifid or three-cleft, and mul- 

 tifid, or many-cleft. 



Laciniate leaves are irregularly divided into numer- 

 ous lobes or segments. In consequence of their ir- 

 regular and indeterminate form, they are also called 

 jagged or incised. 



It has been observed that those submersed leaves 

 which are exposed to the action of running water, are 

 frequently subdivided, while those which float on its 

 quiet surface are large and entire. 



Pinnatifid leaves, Fig. 41, are transversly divided 

 into several oblong, parallel segments, which are grad- 

 ually smaller, as we proceed from the base to the sum- 

 mit of their respective leaves. When these segments 

 are also transversely divided, as in Yarrow, the leaf is 

 said to be Bipinnatifid. When these segments are ex- 

 tremely narrow, and like comb teeth, the leaf is term- 

 ed Pectinate. 



4. COMPOSITION. 



A Compound leaf is Digitate, when several leaflets 

 arise from the summit of a simple petiole, as in the 

 Horse Chesnut, and Hemp. 



It is Binate or Conjugate, when the number of these 

 leaflets is two ; if they are three, as in the Clover and 

 Strawberry, it is Ternate, Fig. 42, and if they are five 

 as in Five finger, it is Quinate. 



It is Pinnate, Fig. 43, if several leaflets arise from 

 the side of a petiole, as in the Rose and Sensitive plants. 

 In the first there is an oJd or terminal leaflet, in the 

 last there is none, and the Rose is said to be oddly, and 

 the Sensitive abruptly pinnate. These leaflets are 

 sometimes opposite and sometimes alternate, and hence 



