350 



Morten P. Porsild. 



The cells in the chlorophyll tissue are parallelepipedic 

 and frequently no intercellular spaces are seen in transverse 

 sections; in longitudinal sections, however, quite small ones 

 are to be seen. The cells of the chlorophyll tissue contain 

 chlorophyll grains filled with starch. In the isolateral part 

 the vascular bundles approach by twos to each other, 

 and the uppermost one is entirely connated of two (Fig. 2 e, 

 3 A). In transverse sections the large, crescent-shaped 

 coverings of bast are to be seen. 



Fig. 3. Anatomy of leaf. 

 A,B,C. T. palustris; from Jakobshavn, W. Greenland. 



A. Transverse section of a foliage leaf above the equitant part. The 

 hatched am is the chlorophyll tissue; the epidermis and the 

 central aqueous tissue are light. 



B. A part of the same section, more highly magnified; ep. Epidermis 

 with thick cuticle and a stoma with very minute air cavity. Chloro- 

 phyll tissue almost without any intercellular spaces, the cells filled 

 with starch ; m aqueous tissue. 



C. Epidermis with two stomata, longitudinally placed. The walls of 

 the cells are highly thickened, slightly undulating. 



D. Transverse section of a leaf of T.coccinea (Danmarks 0, E. Green- 

 land leg. N. Hartz). (Drawn by E. W.) 



The scape of inflorescence is as a rule leaf-less, yet 

 in vigorous specimens 1—2 leaves may be found, the upper- 

 most one at least having the character of a bract (Fig. 1). In 

 T. coccinea 2- — 3 stem-leaves are nearly always present 

 (Fig. 4 ^), the uppermost one having, in this case, less of 

 the character of a bract. 



