- 251 — 



the plant the leaves become narrower with the spine longer; 

 the uppermost leaves as well as the leaves of the rosettes 

 are sessile and acicular as in the previous species. The leaf 

 is not ribbed as in A. minus but the structure of the green 

 tissue is almost the same. The veins have a thick bast- 



Fig. 73. Agriophyllum minus. A, Transverse section 



of leaf, sliowing the distribution of sclerenchyma (black), 



palisades (striped) and veins (N). B, Detail of ^ ; N, 



Veins {A, X 53; 5, X 203). 



sheath and a strand of bast runs along the margin. The 

 stem (fig. 75) has thick hypodermal ribs of sclerenchyma 

 and is better provided with green tissue than the previous 

 species. Lying within the palisade tissue there is a layer of 

 storage cells interrupted by the bast-bundles of the leptome. 



