92 



LEAVES 



portions of the blade of a divided leaf. One result of this differ 

 ence appears in the fact that some time before the whole leaf is 

 ready to fall in autumn, the leaflets of a compound leaf are seen 

 to be jointed at their attachments. In Fig. 99 the horse-chestnut 



FIG. 97. Pinnately com- 

 pound leaf of locust, 

 with spines for stipules 



FIG. 98. Pinnately com- 

 pound leaf of pea 



A tendril takes the place 

 of a terminal leaflet 



leaf is shown at the time of falling, with some of the leaflets 

 already disjointed. 



That a compound leaf, in spite of the joints of the separate 

 leaflets, is really only one leaf is shown : (1) by the absence of 

 buds in the axils of leaflets (see Fig. 97) ; (2) by the horizon- 

 tal arrangement of the blades of the leaflets, without any twist 

 in their individual leafstalks ; (3) by the fact that their arrange- 

 ment on the midrib does not follow any of the systems of leaf 



