SELAGINELLA 



165 



become mature. This outgrowtli is called the Ugule 

 (literally, a tongue), and it is a regular feature through- 

 out the genus. In the figure, r points to the rhizophores 

 (root-bearers) arising from the stem; these seem like 

 roots, for they are destitute of leaves, and colourless; 

 they reach down to the soil, and it is on touching it that 

 they give rise to true rootlets, which branch from them 





Fig. 54. — Selaghtella Kbaussiana. 

 r, Rhizophores; s, spikes. 



and penetrate the ground. Certain branches are erected 

 from the creeping stem, and bear the fruiting spikes, or 

 cones (Fig. 54, s). The leaves of the cones are sporo- 

 phylls; they bear the sporangia in their axils. The 

 sporangia are slightly stalked, and of two kinds — micro- 

 sporangia and megasporangia. The former contain a 

 great number of microspores; the latter have only four 



