Lecture XIX. 



147 



off. These are dark brown in colour, cord-like and almost wiry 

 in consistency. The soft tissues and young leaves are at the 

 top and the hard material and old leaves at the base of the stem. 

 Evidently it grows at the top and there forms the new leaves. 



The relation of the leaves to the stem is best seen by splitting 

 the latter down longitudinally. The upper part of the stem is 

 composed of whitish, cheese-like and somewhat slimy tissue. 



FIG. 32. Aspidiiim filix-mas : on the right, stem cut longitudinally, x 3. 

 a, net -work of conducting tracts ; b, branches from net-work supplying 

 leaves ; c, young leaves curved over apex ; /, fundamental tissue ; 

 /, meshes of net- work forming leaf-gaps; r, conducting tract of root; 

 on the left is shown the net-work with the fundamental tissue removed. 



The extreme top is a low cone. Viewing the cut surface with a 

 lens small prominences on the side of this cone may be made 

 out. These prominences are the beginnings of leaves which 

 in a year's time will have grown into small incurved leaves, 

 similar to those which now are seen outside them curving 

 over the top. In the meantime those which are now in this 

 position will have developed into mature foliage-leaves. The 



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