53^ 
PHANEROGAMS. 
the cup thus formed encloses the carpels (as in perigynous flowers), or even takes 
part in the formation of the ovary, which is then inferior (Fig. 358). The result of 
this abbreviation of the axis is that the separate parts do not usually stand one above 
another, but rather in concentric whorls, or in scarcely ascending spirals, for which 
reason the explanation of the relative positions expressed by a diagram in the sense 
explained on p. 188 appears the most obvious. This abbreviation of the axis is also 
obviously the immediate cause of the numerous cohesions and displacements which 
are nowhere met with so frequently as in the flowers of Angiosperms. The small 
development of the floral axis in length depends on the early cessation of its apical 
growth; the acropetal or centripetal order of succession of the floral leaves may 
therefore be disturbed ' by the production of intercalary zones of growth, although 
even in these cases the disturbance of the ordinary regularity remains inconsiderable. 
The acropetal order of succession is however even here in most cases strictly carried 
out, and the apical growth of the floral axis not unfrequently continues long enough 
Fig. ^e^g.~ChcnoJ)odin7n Quüioa; /—/^'' development of the flower {in longitudinal section), if the calyx furnished 
with glandular hairs k, a anthers, k carpels, sk ovule, x apex of the floral axis, horizontal section of an anther 
with four pollen-sacs on the connective oti (strongly magnified). 
to allow the foliar structures to arrange themselves in evident whorls placed one over 
another or in spirals {e.g. Magnolia^ Ranunculaceae, Nymphaeaceae). Occasionally 
also particular portions of the axis are greatly elongated within the flower, as the 
portion between calyx and corolla in Lychnis (Fig. 361), in Passiflora that between 
corolla and stamens, in Labiatse that between stamens and ovary. 
The flower of Angiosperms, like that of Gymnosperms, is a metamorphosed 
shoot, a leaf-bearing axis ; but this section of the vegetable kingdom is especially 
characterised by the high degree of metamorphosis which the floral shoot has 
undergone, and by the very peculiar characteristics and the diff'erent arrangement 
of the foliar structures as contrasted with those of the purely vegetative shoots. 
As far as external appearance goes, the flower of Angiosperms is an altogether 
^ The cases adduced by Hofmeister (Allgemeine Morphologie, § 10) of the absence of strict 
acropetal succession in the foliar structures all belong to this category. 
