LEAF-BRANCHES 



107 



225. The foliage 

 of asparagus is com- 

 posed of modified 

 branches. The true 

 leaves of asparagus 

 are minute whitish 

 scales, (a, Fig. 159.) 

 The green foliage is 

 produced in the axils 

 of these scales. On 

 the strong spring 

 shoots of asparagus, 

 which are edible, the 

 true leaves appear as 

 large scales, (a, a, 

 Fig. 160.) These 

 large scales persist on the base of 

 the asparagus plant, even in the 



fall. In the species of greenhouse or ornamental 



asparagus, the delicate foliage is also made up of 



green leaf-like branches. (Fig. 161.) In some cases 



the true leaves fall after a time, and there is little 



evidence left. The strong new shoots usually show 



the true leaves plainly (as in Fig. 162). Branches 



that simulate leaves are known as cladophylla 



(singular, cladophyllum). The broad flat leaves 



of florists' smilax (common in glasshouses) are 



cladophylla. 



226. In the study of morphology, it is not 

 enough, however, merely to determine 

 whether a part represents root, stem or 

 leaf: one must determine what part or 

 kind of root, stem or leaf it stands for. 

 For example, the foliage in Fig. 163 rep- 

 resents green expanded petioles. These 



163. Phyllodia of aca- 

 cia. These Australian 

 trees are sometimes 

 grown in glasshouses. 



