LOSS OF WATER 29 



petiole may take on the character of the blade, and perform 

 all its functions, as in the case of various acacias. In certain 



FIG. 20. Tulip bulb; longitudinal section. F, solid stem; B, flower 

 bud; S, leaf-bases serving as bud-scales, and also for the storage of plant 

 food. 



leaves nothing remains but base, petiole, larger veins, and 

 the tips of the blade, as in the New Zealand raspberry 



FIG. 21. Buds of the tulip-tree (Liriodendron tulipifera), showing stipules 

 as bud-scales. 



(Fig. 1 8). In some plants, as for example, the grasses 

 (Fig. 22), there is no distinction between petiole and blade. 



