OBSERVATIONS ON THE STEM STRUCTURE OF 

 HEMITELIA C A PENS IS. 



By H. S. Morris 



Hemitelia Capensis is a fine tree fern found growing in several 

 parts of the Table Mountain range. The average height to the 

 crown of the stem is about five feet, but maj^ in some specimens 

 be as much as eight feet. The stem is clothed with decayed leaf- 

 bases, closely crowded together, and, including these, has a diameter 

 of from 4 to 4^ inches ; but the stem proper is about 3 to 3^ inches 

 through. 



The stem itself is composed of an outer hard fibrous layer, dark 

 brown in colour, enclosing a narrow zone of white parenchymatous 

 starchy ground tissue, and within this is a thick stelar cylinder 

 perforated by circular foliar gaps, and appearing in transverse 

 section as a broken ring of large steles. Four or five foliar gaps 

 are usually shown in one section, the margins of the steles bend- 

 ing out towards the fibrous layer (fig. i). This cylinder encloses 





Fig. I. 



a large mass of the ground tissue containing man\' small circular 

 bundles, frequently in pairs, and some of these, more especially 

 the larger ones nearest the bundle tube, are leaf traces. All the 

 steles are concentric and completely enclosed by a thick la3'er 

 of brown Sclerenchyma. 



Two leaf traces pass into each leaf through the foliar gap and 

 are peculiar. Each comes in contact with the top margin of the 

 gap as it passes through and fuses with the main tube, the scleren- 

 chyma and phloem successively disappearing between them, the 

 xylem thus becoming continuous. Each leaf trace at this point 

 presents the appearance of having been incompletely constricted 

 off from the edge of the large stele, but this is not the case. The 

 pair are labout two lines separate as they enter the leaf and do 



