Betts. — Autecology of Plants of Peridotite Belt, Nelson. 



291 



Both the upper and the lower epidermis consist of very regular cells, 

 the walls of which are only slightly thickened. On both surfaces there is a 

 thin cuticle, and on the lower (the outer) surface there are a number of 

 hairs like those on the lower surface of the leaf. 



Beneath the upper epidermis there is a hypoderma which is composed 

 of a single layer of small sclerized cells in which the walls are very thick 

 and the lumen very small. 



Fig. 18. — Celmisia longifolia var. gracilenta. Transverse section of peduncle 

 (X 230). a, multicellular hairs; b, ridged cuticle'; c, unlignified 

 cortex ; d, lignified cortex ; e, xylem ; /, phloem. 



The vascular bundles are of the same type as that described for the 

 leaves, but the stereome above the xylem and below the phloem is formed 

 of much smaller cells than in the leaf. All the mesophyll consists of. 

 aqueous tissue, which is composed of thin-walled, colourless cells. Near 

 the lower surface there are 2 rows of these cells, which are regularly 



10* 



