352 



towards the circumference have somewhat thickened walls. The 

 bundles number between 10 and 16; some wood-parenchyma 

 occurs between the sieve-tissue and the vascular woody part 

 from which non-lignified parenchyma was wanting, and, as was 

 the case in several other species, some small-celled, somewhat 

 collenchymatous parenchyma occurs on the inner side of the 

 bundles (Fig. 10, B). In the peduncle there is no distinct 

 sheath between the conducting tissue and that around it. The 

 young flower-stalk has almost no stereom. In the older stem 

 there is a large central lacuna. 



Fig. 10. R. affinis. 



A, Transverse section of rhizome (Gâselandet; "/i). e, Endodeimis; ph, leptome; x. 



xylem. B, Portion of transverse section of stem (Cape Thordsen; ^"/1). ep, Epidermis; c, 



cortex; b, bast; ph, leptome; vp, lignified parenchyma; x, xylem; ):p, collenchymatous 



parenchyma; end, endodermis. 



Var. Wilcmderi was somewhat more compact in structure 

 than was the principal form. 



The thickness of the leaf varies from 210 to 250//, and 

 the specimens investigated show greater differences among 

 themselves in the structure of their leaves than is the case 

 in any other species. The epidermis however is nearly alike 

 in all the specimens ; it contains chlorophyll, and the radial 

 walls are more or less acutely-undulating, those of the lower 

 surface somewhat more strongly so than are those of Ihe upper 

 surface (Fig. l\.A,B); the radial walls are also often perforated 

 and are often thickened on one side in the angles; the lateral 



