.128 Shaw—Structure of the Flowers in 
The axis bearing the evident flowers is rather sharply three- 
angled and slightly winged. In the phloem the indurated 
layer forms a nearly continuous ring. 
The axis bearing the aérial cleistogamic flowers is smaller 
in diameter and faintly three-angled, two angles being more or 
less winged. The induration of the phloem is not so great. 
The axis bearing the subterranean cleistogamic flowers is 
variable in size, but averages considerably larger than the 
preceding. It is elliptical in section, and there is scarcely 
any induration in the phloem. The cortical parenchym is 
very loose and spongy, and the external cuticle only faintly 
formed. Sometimesthe medulla is almost obliterated, and the 
wood then appears as a central strand. 
Bracts.—Small bracts are present in the evident raceme, but 
they fall away about the time of flowering. Inthe racemes 
of both sorts of cleistogamic flowers, they are persistent as 
small scales. 
Calyx.—A. The Chasmogamic Flower. In this the three 
outer sepals are small, green, 1%4-2 millimeters long, 24-1 
millimeter wide. The two inner sepals or wings are large, 
pink-purple, and projecting beyond the corolla and stamens 
enclose these inner members. The posterior one is slightly 
larger. Referring for a moment to the foliage leaf, its epi- 
dermis is composed of cells with wavy outlines and peculiarly 
thickened walls, as shown in Plate XVII, Fig 10. Stomata 
are found over both surfaces. In comparison with the foliage 
leaf both upper and lower epidermis of the three outer sepals 
consist of wavy-walled cells, rather like those of the lower 
leaf epidermis, but more elongated. The walls, perpendic- 
ular to the surface, have not the peculiar, inwardly projecting 
thickenings of the former. The outer epidermis is well 
supplied with stomata, especially in the middle region. On 
the inner surface the stomata are rare. 
