128 



MANUAL or BOTANY 



relatively few large, often pinnate, loaves. In some ferns the 

 stem branches normally, the branch system being lateral and not 

 dichotomoiTS as in the lower groups ; in others the branching is 



-st 



Fig. 885. 



Fig. 884. Polystelic stem of Fern. st. Steles, sc. Bands of selerenchyma. 



hy, Hypodermal selerenchyma. ep. Epidermis. Fig. 886. Stele of stem 



of Tern, composed of three fused concentric bundles, en. Endodennis. 

 ipe. Pericyle, pU. Phloem, pz. Groups of protoxylcm. 



en. 



adventitious. The roots are always adventitious, for though a 

 primary root is always, developed it never persists in the adult 

 fern. The adventitious roots are small and often branched, 

 arising in great numbers from the stem or the leaf stalks. The 



