29.; 



CHAPTER II. THE TISSUES. 



143 



either unicellular or multicellular. When the multicellular hair 

 consists of a single row of cells, the secretion is generally confined 



.jpV^Lyl^. . ; L^^ 



FIG. 107. (Highly magnified, after Dippel). A Part of a laticiferous coenocyte of Euphor- 

 bia splendens. In the latex are peculiar rod-shaped starch-grains. B Network of latici- 

 ferous vessels from the root of Cichorium Intybus. 



either to a large terminal cell, or to several of 

 the distal cells ; in any case the secretion begins 

 with the terminal cell, and extends backwards to 

 other cells towards the base. The gland, though 

 epidermal in origin, does not, however, always 

 project from the surface, but may be more or 

 less sunk in the internal tissue {e.g. glands in the 

 leaf of the Psoralea Tiirta). 



The secretum (which may consist of mucilage, 

 or gum-resin, or ethereal oil, balsam, etc.) is 

 accumulated either in the cavity of the secreting 

 cells (e.g. mucilaginous hairs at the growing- 

 point of Liverwort-gametophytes and of Fern- 

 sporophytes), or between the external cuticle and 



FIG. 108. Glan- 

 dular hair from the 

 base of a ramentum 

 of Aspidium Filiei 

 mas (x200): 8, the 

 secretum, lying be- 

 tween the outer and 

 inner layers of tbe 

 cell-wall, c and m. 



