LEAVES. 



[SECTION 



feath>-f-r<-i,ied (i. e. j>itiiin/rfi/-veitted) simple leaf; as will be seen at once 

 on comparing the forms. The leaflet* of llic former answer to the lobes or 

 .lirixionii of the latter; and tin: continuation of the petiole, along which the 

 i, a, Ids arc arranged, answers to the midrib of the simple leaf. 



150. Three sorts of pinnate leaves are here given. Fig. 15G is pinnate 

 trith cm odd or end l-djlet, as in the Common Locust and the Ash. Pig. 

 157 is pinnate with a tendril at the end, in place of the odd leaflet, as in 

 [he Vetches and the Pea. Tig. 158 is evenly or abruptly pinnate, as in the 

 Honey-Locust. 



151. Palmate (also named Digitate) leaves are those in which the leaf- 



lets are all borne on the tip of the leaf- 

 stalk, as in the Lupine, the Common 

 Clover, the Virginia Creeper (Fig. 93), 

 and the Horse-chestnut and Buckeye 

 (Fig. 159). They evidently answer to 

 the radiate-veined or palmately-veined 

 simple leaf. That is, the Clover-leaf of 

 three leaflets is the same as a palmately 

 three-ribbed leaf nit into three separate 

 leaflets. And such a simple fivc-lobed 

 leaf as that of the Sugar-Maple, if 

 more cut, so as to separate the parts, 



would produce a palmate leaf of five leaflets, like that of the Horse-chestnut 



or Buckeye. 



152. Either sort of compound leaf may have any number of lenflets ; yet 

 palmate leaves cannot well have a great many, since they are all crowded 

 together on the end of the main leaf-stalk. Some Lupines have nine or 

 eleven; the Horse-chestnut has seven, the Sweet Buckeye more commonly 

 five, the Clover three. A pinnate leaf often has only seven or live leaflets, 

 or only three, as in Beans of the genus Phascolus, etc. ; in some rarer cases 

 only two; in the Orange and Lemon and also in the common I'.arbcrry 

 there is only one! The joint at the place where the leaflet is united with 

 the petiole distinguishes this last case from a simple leaf. In other species 

 of Ihcse genera the lateral leaflets also are present. 



1.-,:$. The leaflets of a compound leaf may be either entire (as in Fig. 

 1-V.-128), w serrate, or lobed, cleft, parted, etc.; in fact, may present all 

 the variations of simple leaves, and the same terms equally apply to them. 



154. When the division is carried so far as to separate what would be 

 one leaflet iulo two, three, or several, the leaf becomes <!,,<i!,h/ or linec 

 wnd, either phtnalely or palmnfeh/, as the case may be. For example, 

 while the clustered leaves of the Honey-Locust are simply pinnate, thai is, 

 oner pinnate, those on new shoots are f>ipinafe, or tines pinnate, as in 

 l"i- K,0. When these leaflets are again divided in the same way, the leaf 



Fiu. 159. I'ulmair (,,r digitate) 1-al' <!' live l.MiMs, f Hie Swcrt Buckeye. 



