. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. CONIPERALBS 75 ment of bundles in the arc showing that the axillary structure is a leaf and not a branch; and that the reversed orientation shows that the leaf belongs upon the suppressed branch opposite the bract. This is not Robert Brown's view of an axillary car- pel, but rather Alexander Braun's view that the ovuliferous scale is the leaf of an axillary branch. In 1871 Von Mohl ^* further strengthened Braun's position by the publication of his studies of the peculiar " double leaf " of Sciadopit
. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. CONIPERALBS 75 ment of bundles in the arc showing that the axillary structure is a leaf and not a branch; and that the reversed orientation shows that the leaf belongs upon the suppressed branch opposite the bract. This is not Robert Brown's view of an axillary car- pel, but rather Alexander Braun's view that the ovuliferous scale is the leaf of an axillary branch. In 1871 Von Mohl ^* further strengthened Braun's position by the publication of his studies of the peculiar " double leaf " of Sciadopitys. He showed that this leaf represents the first two leaves of an axillary shoot, which stand transversely, and which become coalescent by their posterior (toward the axis) edges, the vascular bundles thus showing reversed orientation. As this normal behavior of the leaves of Sciadopitys exactly parallels what was claimed by Braun for the ovuliferous scale, the results of Von Mohl are almost in the nature of a demon- stration. In 1872 Strasburger ^'^ announced his adherence to the view that the ovuliferous scale is a flattened axis, at the same time combating the idea of gymnospermy. While later ^* his views. ABC Fio. 60.—Microsporangia from the strotili shown in Fig. 59: A, normal sporophyll, side view; S, slightly modified sporophyll from summit of a bisporangiate stro- bilus; 0 and D, side and front views of sporophylls from summit of a bisporangiate strobilus; E and F, side and front views of sporophylls from the base of a bispor- angiate strobilus. in reference to gymnospermy became modified, he held to the axial nature of the scale. In 1876 Stenzel ^° described striking abnormalities in Picea excelsa. In one cone leafy axes occurred in the axils of the bracts, the first two leaves resembling ovuliferous scales more than ordinary foliage leaves in texture. In other cones the abnormalities recorded by Dickson ^ were observed. In still. Please note that these images are
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