402 



Fr. J. Mathiesen. 



cular striations, and small glandular hairs with one-celled 

 stalk and two-celled head. The cortex is few-layered (3—4 

 cell-layers in thickness) as in the root; in the endodermis 

 the Casparian dots are faint, but nevertheless demonstrable 



Fig. 14. Euphrasia arctica. 

 A, Epidermis of the upper, and В of the lower surface of the leaf. 

 C, Transverse section of the leaf. D and E, Glandular hairs from the 

 lower surface of the leaf. F, A glandular hair from the margin of the 

 leaf. G, A 2-celled, non-glandular hair. (A, B, C, D, E, F and G about 

 11%). (Greenland.) 



with Sudan III. The pericycle is 1 — 2 layered. The outer 

 part of the rather broad ring of xylem is composed exclusively 

 of wood-fibres. The peripheral cells of the pith have some- 

 what thickened walls. Medullary rays are absent. 



The Leaf. A transverse section of one of the lower 

 foliage-leaves is shown in Fig. 14, 6'; there occur 1 — 2 layers 



