. Carnegie Institution of Washington publication. V)2 I III MARAT! S younger leaf. Fig. 175, E, shows .1 young leaf from anothei plant, in which one siilc has been cut away so as to show the relation of the stipules to the leaf base. This leal 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 in Botrychium and Helminthostachys, and there is no reason to suppose that it is not exactly homologous with this.
. Carnegie Institution of Washington publication. V)2 I III MARAT! S younger leaf. Fig. 175, E, shows .1 young leaf from anothei plant, in which one siilc has been cut away so as to show the relation of the stipules to the leaf base. This leal 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 in 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 youngei leaf, which is cut in a plane nearly at 11 lclit 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. ljv H, /-'). Within the stipular sheath of this leaf is a still younger one, which is entirely concealed from view from the outside, hut shows plainly in longitudinal sections, taken next to the center of the hud. The stem apex is entirely concealed within the sheath of the younger leaf. The resemblance of this section of. Fig. 175.âMarattia alata Smith. A, B. Young plant developed us a bud upon an old leaf base. The outer tissue bas been cut away, and the two sides of the thick central section arc shown. XI. C. Section "t petiole of leaf. D. Three sections of a rhizome of a small plant. :â : i.;; E. Youne. leaf. The lamina is coiled up within the large stipules, si. In (l) one of the stipules has been cut away to show the commissure, com. Xi.;; the young plant to a similar section of the hud in one of the larger species of Botry- chium or of Helminthostachys is sufficiently striking. I he bundles forming the ting in the petiole anastomose freely in the leaf base, as they do in Kaulfussta or Ophioglossum pendulum, so that the number of strands in the leaf trace is smaller than the number of bun
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
