98 



THE OPHIOGLOSSALES 



The anatomy of O. simplex, so far as it has been investigated (see Bower 8) 

 corresponds closely with that of the other species of the section Ophioderma. 



The roots of 0. pendulum also show the tetrahedral apical cell (fig. 67), but the 



divisions are much less regular than in 

 O. moluccanum and probably the other 

 species of the Euophioglossum. The 

 segments divide slowly and increase a 

 good deal in size before the first divi- 

 sions take place, so that the youngest 

 segments may equal the apical cell in 

 size, and there is thus a certain resem- 

 blance to the apical meristem in the 

 root of the Marattiaceae. It is prob- 

 able that, as in the Marattiaceae, the 

 lateral segments of the apical cell also 

 contribute to the root cap, which is 

 rather better developed than it is in 

 O. moluccanum. 



There is a good deal of difference 

 in the structure of the root bundle 

 (fig. 68). This is diarch in the primary 

 root, as we have seen, and also in the 

 smaller ones of older sporophytes; but 

 in the larger roots, which may reach 

 a diameter of over 3 millimeters, it is 

 triarch; tetrarch bundles are also com- 

 mon, and in one very large root which 

 I examined the bundle was pentarch, 

 but one of the xylem rays was shorter than the others, the xylem forming a solid 

 central mass having the form of an irregular five-pointed star. 



Five specimens of 0. intermedium Hk., slightly reduced. 

 C and D have a very much reduced lamina. 



Fig. 70. 



A. Small plant of Ophioglotsum palmatum L., growing as a bud upon a root fragment 



B. Hairs from base of leaf. X35. 



C. Section of petiole of a large leaf. X7.5. 



