Primulaceae. 



207 



cover-hairs on both surfaces of the leaf. The epidermal cells 

 from which the cover-hairs originate, are strongly arched. 

 Stomates are present in great numbers on both surfaces. 

 Where the leaves are pressed closely together in rosettes, 

 the proportion between the number of stomates on the upper 



Fig. 22. Androsaces chamaejasme. 

 Ä, the epidermis of the lower surface of the leaf. B, the epidermis of the upper surface 

 of the leaf. C. a piece of the epidermis, more enlarged. D and E, forms of glandular 

 hairs. jF, cover-hairs from the margin of the leaf, seen in optical section. G, transverse 

 section of the leaf. H, a single stoma. (Ä, В and G, obj. 8, oc. 4; F, obj. 8, oc. 6; C, D, 

 E and H, obj. 4, oc. 4.) (Jugor Schar.) 



and lower surface is almost the same, but they are always 

 somewhat more numerous on the lower surface. On shoots 

 with few leaves (see fig. 19, A, furthest to the right), the 

 stomates are much fewer on the upper than on the lower 

 surface of the leaves; but, in this case the stomates are 



