. Carnegie Institution of Washington publication. 61. Five sections of a full-growD sporophyl] of 0phioglouum woluccanutt K, m-iNhum! pr,luiuic of spike; /. ' not easily determined. The cortical cells inside the mycorrhizal zone an- densely filled with starch. More than half of the section of the bundle is occupied by the huge solid mass of wood. This is separated from the endodermis by a single layer of pericyele cells. The single mass of phloem King next the wood is not much more than half as large. \\ \K)\1V OF OPHIODERMA. Owing to the dorsiventral position of the rhizome and to
. Carnegie Institution of Washington publication. 61. Five sections of a full-growD sporophyl] of 0phioglouum woluccanutt K, m-iNhum! pr,luiuic of spike; /. ' not easily determined. The cortical cells inside the mycorrhizal zone an- densely filled with starch. More than half of the section of the bundle is occupied by the huge solid mass of wood. This is separated from the endodermis by a single layer of pericyele cells. The single mass of phloem King next the wood is not much more than half as large. \\ \K)\1V OF OPHIODERMA. Owing to the dorsiventral position of the rhizome and to the more rapid de- velopment of the leaves, the section of the stem apex in Ophioglossum pendulum differs a good deal from a similar section of Euophi0glossum (fig. 64). The base of' the leaf is bent sharply upward, this being the case also in the very young leaf which is inclosed within the bud. The leaves break throujdi the inclosing sheath in a vcrv rudimentary condition, although of such size that a section through the base of the youngest visible leaf shows usually but a single younger leaf inside the sheath, instead of the three 01 four that are seen in a similar section of tin bud in Euophioglossum. Within the sheath at the base of the youngest visible leaf there is found a cavity in which is the growing point of the stem and the youngest leaf. The apex of the stem forms a strongly inclined, nearly plane surface and, as in Euophioglossum, the growth is from a single apical cell which, so far as could be deter- mined, has the form of a three-sided pyramid, whos< lateral faces are more or less strongly convex and whose apex may be truncate. From the few cases observed it is not possible to say definitely whether basal seg- ments are regularly cut off as well as the lateral ones. The segments cur oft from the lateral faces are large and the divisions irregular. Owing to the large size of the sporophyte there are practical difficulties con- nected with the study of the v
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
