VIII 



THE P TERID OPH VTA — OPHIO GL OSS A CEA: 



235 



mingled irregularly with smaller cambiform cells. Whether or 

 not sieve-tubes occur upon the inner side of the bundle could 

 not be positively determined. The sporangiophore has much 

 the same anatomical structure as the rest of the leaf, but stomata 

 are quite absent from its epidermis. In this respect O. pendulum 

 differs from O. vulgatuvi and allied species, where stomata are 

 developed upon the sporangiophore as well as upon the rest of 

 the leaf. 



TJie Root 



The roots are formed singly near the bases of the leaves, 

 and are light yellowish brown in colour, and so far as could be 



7 IG. T.ii.— Oj>hioglossuiit pendnhnnih.). A, Longitudinal ; B, transverse sections of the root apex, X 215. 



seen, entirely unbranched. Sections show that here, as in most 

 vascular plants, the growing point of the root is not at the apex, 

 but some distance below and protected by the root-cap. The 

 growth of the root in OpJiioglossuin can be traced to a single 

 apical cell (Fig. Ii8), which is of large size, and, like that of 

 the stem, approximately pyramidal in form. While the divi- 

 sions show greater regularity than in the stem, still they are 

 very much less so than in the higher Ferns. Segments are 

 here cut off not only from the lateral faces of the apical cell, 

 but also from its outer face. These outer segments help to 

 form the root -cap, which, however, is not derived exclusively 

 from these, but in part also from the outer cells of the lateral 



