LESSON 9.] 



COMPOUND LEAVES. 



164. The separate pieces or little blades of a compound leaf are 

 called leaflets. 



165. Compound leaves are of two principal kinds, namely, the 

 pinnate and the palmate ; answering to the two modes of veining in 

 reticulated leaves (145-147), and to the two sorts of lobed or di- 

 vided leaves (153, 159). 



166. Pinnate leaves are those in which the leaflets are arranged 

 on the sides of a main leaf-stalk ; as in Fig. 126 - 128. They answer 

 to the feather-veined (\.e.pinnately-veined) simple leaf; as will be 

 seen at once, on comparing Fig. 126 with the figures 118 to 121. 

 The leaflets of the former answer to the lobes or divisions of the 

 latter ; and the continuation of the petiole, along which the leaflets 

 are arranged, answers to the midrib of the simple leaf. 



167. Three sorts of pinnate leaves are here given. Fig. 126 is 

 pinnate with an odd or end leaflet, as in the Common Locust and 

 the Ash. Fig. 127 is pinnate with a tendril at the end, in place of 

 the odd leaflet, as in the Vetches and the Pea, Fig. 128 is abruptly 

 pinnate, having a pair of leaflets at the end, like the rest of the leaf- 

 lets ; as in the Honey- Locust. 



168. Palmate (also named digitate) leaves are those in which the 

 leaflets are all borne on the very tip of the leaf-stalk, as in the 

 Lupine, the Common Clover (Fig. 136), the Virginia Creeper (Fig. 

 62), and the Horsechestnut and Buckeye (Fig. 129). They answer 

 to the radiate-veined or palmately- 



veined simple leaf; as is seen by 

 comparing Fig. 136 with the figures 

 122 to 125. That is, the Clover- 

 leaf of three leaflets is the same as 

 a palmately three-ribbed leaf cut 

 into three separate leaflets. And 

 such a simple five-lobed leaf as that 

 of the Sugar-Maple, if more cut, so 

 as to separate the parts, would pro- 

 duce a palmate leaf of five leaflets, 

 like that of the Horsechestnut or Buckeye (Fig. 129). 



169. Either sort of compound leaf may have any number of leaf- 

 lets ; though palmate leaves cannot well have a great many, since 

 they are all crowded together on the end of the main leaf-stalk. 



FIG. 120. Palmate leaf of five leaflet, of the Sweet Buckeye. 

 6* 



