THE STEM 



61 



97. A scaly bulb (like that of the Lily, Fig. 51), is one iii which 

 the scales are thick but comparatively narrow. 



98. A tunicated or coated bulb is one in which the scales enwrap 

 each other, forming concentric coats or layers, as in Hyacinth and 

 Onion. 



99. Stems as foliage. — All green parts of the plant, 

 whether belonging to the leaf or to the stem, serve the 

 same purpose as the foliage to some extent ; for example, 

 the green twigs of a tree and the green stem of an herb. 



52. Flattened leatlike stems of MuhlenhecTcia platy- 

 claclos, bearing flower clusters at the nodes. 



A considerable number of plants have come to dispense 

 with leaves entirely, modified stems doing their work. 

 Thus, in the Asparagus what appear to be needle-like 

 leaves are in reality branches springing from the axils of 

 the true leaves; the leaves themselves being minute, dry 

 scales. In Muhlenbeckia (Fig. 52) the nodes of the stem 



