J92 THE MARATTIALES 



younger leaf. Fig. 175, E, shows a young leaf from another plant, in which one 

 side has been cut away so as to show the relation of the stipules to the leaf base. 

 This leaf was still coiled up and its apex was quite concealed within the large 

 overlapping stipules. Both as to its position and its relation to the stipules, the 

 commissure exactly resembles the lip-like basal extension of the stipular sheath m 

 Botrychium and Helminthostachys, and there is no reason to suppose that it is not 

 exactly homologous with this. 



Partially inclosed by the stipular sheath of the expanded leaf is the next younger 

 leaf, which is cut in a plane nearly at right angles with that of the oldest leaf, so that 

 the overlapping of the stipules, which entirely conceal the rest of the leaf, is very 

 plainly seen (fig. 175, B, /=). Within the stipular sheath of this leaf is a still younger 

 one, which is entirely concealed from view from the outside, but shows plainly in 

 longitudinal sections, taken next to the center of the bud. The stem apex is entirely 

 concealed within the sheath of the younger leaf. The resemblance of this section of 



Fig. 



175- 



-Marattia alata Smith. 



A, B. Young plant developed as a bud upon an old leaf base. The outer tissue has been cut away, and the two sides 

 of the thick central section are shown. XI. 



C. Section of petiole of leaf. 



D. Three sections of a rhizome of a small plant. X1.33 



E. Young leaf. The lamina is coiled up within the large stipules, st. In (i) one of the stipules has been cut away 



to show the commissure, com. X1.33 



the young plant to a similar section of the bud in one of the larger species of Botry- 

 chium or o{ Helminthostachys is sufficiently striking. 



The bundles forming the ring in the petiole anastomose freely in the leaf base, 

 as they do in Kaulfussia or Ophioglossum. pendulum, so that the number of strands 

 in the leaf trace is smaller than the number of bundles within the petiole. 



The vascular bundles in the stem form a single very open mesh-work, with 

 which the leaf traces join and which is, with little question, composed entirely of 

 these leaf traces, as it is in the earlier stage. Indeed, except for the larger size of 

 these plants, there is no essential difference between them and the young germ 

 plants, described in M. douglasii. Several roots are usually developed before the 

 first leaf of these young bud-plants unfolds. Probably one root develops for each 

 leaf, but it is not certain that this is always the case. Owing to the thickness of the 

 cortical region which has to be traversed by the root before it emerges, the roots 

 have already reached a large size before they appear upon the outside. This deep- 



