. Dansk botanisk arkiv. Plants; Plants -- Denmark. of one-celled acute teeth. A transverse section at the middle (Fig. 27 a) shows that the middle vein is somewhat nearer the one margin than the other. This obliqueness is more pronounced in a transverse section near the base where the ear-shaped part is met with (Fig. 27 b). Here the middle vein is found in the upper half of the clasping leaf-base. The first leaves of an assimilative are transitional in form between the scale of the rhizome and the foliage leaves. pairs are somewhat distant in the lower part of the pressure of the the assimila
. Dansk botanisk arkiv. Plants; Plants -- Denmark. of one-celled acute teeth. A transverse section at the middle (Fig. 27 a) shows that the middle vein is somewhat nearer the one margin than the other. This obliqueness is more pronounced in a transverse section near the base where the ear-shaped part is met with (Fig. 27 b). Here the middle vein is found in the upper half of the clasping leaf-base. The first leaves of an assimilative are transitional in form between the scale of the rhizome and the foliage leaves. pairs are somewhat distant in the lower part of the pressure of the the assimilative shoot; further up they are more closely placed, partly covering one another. Probably the assimilative shoots are comparatively short-lived, while the creeping rhizome steadily renews itself by new shoots, the ulder dying away behind. Towards the apex of some assimila- tive shoots male flowers were present in the axils of the leaves, and owing to I heir presence the regular edgewise arrange- ment of the leaves is somewhat disturbed. The flowers press the leaves apart, and by this pressure the upper part of the shoot becomes more or les spirally twisted (Fig. 29). The male flower is placed solitary in the axil of an ordinary foliage leaf, and is enclosed in a two-leaved in- volucrum (Fig. 30). The outer in- volueral leaf is nearly two-keeled (one acute and one blunt angle) with a flat back; towards its apex it is somewhat spinulose-serrate (Fig. 30a). The inner involucraJ leaf encloses the flower bud; it is one-keeled and has a long-pointed apex (Fig. 306). The flower itself consists of three perianth leaves which, when they open, bend backwards and force the edgewise- Fig. 31. Halophila spinulosa. Truns- verse section through a male set leaf a little aside. The perianth flower, showing the two involucral leaves are obtuse ovate-oblong leaves, the three-leaved perianth . ., i t -i .i • and the three anthers. (About lamtly one-nerved. Inside the peri- »/ nat. size). Fig.
Size: 1622px × 1541px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectio, bookdecade1910, booksubjectplants
