. Morphology of gymnosperms. Gymnosperms; Plant morphology. 172 MORPHOLOGY OF GYMNOSPERMS of mycorhiza had been reported previously from the Coal-measures, this observation is one of special interest. 2. The spore-producing members THE STROBILI The small strobili, not often more than a centimeter in length, are borne laterally upon short, simple or branched, lateral shoots (fig. 204). These strobilus- bearing branches suggest in- florescences; and although \ —'w^^kMm^^^^^ occurring among the leaves, '^ ^ they do not always seem to be axillary. These structures were recorded under the general n
. Morphology of gymnosperms. Gymnosperms; Plant morphology. 172 MORPHOLOGY OF GYMNOSPERMS of mycorhiza had been reported previously from the Coal-measures, this observation is one of special interest. 2. The spore-producing members THE STROBILI The small strobili, not often more than a centimeter in length, are borne laterally upon short, simple or branched, lateral shoots (fig. 204). These strobilus- bearing branches suggest in- florescences; and although \ —'w^^kMm^^^^^ occurring among the leaves, '^ ^ they do not always seem to be axillary. These structures were recorded under the general name Antholithus until Grand 'Eury found Antho- lithus in connection with the leaf-bearing shoots of Cor- daites. Since many of the, strobili cannot be referred with certainty as yet to the definite species of Cordaitales, the form genus Cordaianthus has been used to record most of them. Our knowledge of the internal structure of Cordaianthus has come chiefly from the few sections made by Renault (3). Both kinds of strobili are sheathed by bracts, so that it is not always possible to distinguish them externally. THE MICROSPORANGIUM In Cordaianthus Penjonii (fig. 205) the staminate strobilus (i cm. long) consists of a thick axis bearing spirally arranged bracts, among which stamens are inserted. The stamens are either solitary or are grouped near the apex of the axis. Each stamen consists of a more or less elongated stalk bearing at its tip a cluster of three to six erect sporangia (fig. 206). The wall of the sporangium is a single layer. Fig. 204.—Cordaites: portion of stem showing one leaf and' four branches, each branch bearing numerous strobili; Xj.— After Grand 'Eury (2).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John Merle, 1851-1928; Chamberlain, Charles Joseph, b. 1863; Coulter, J
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