520 
CHRIST] NE E. QUINLAN ON 
of lignification. The cortical parenchyma,, seen in transverse section, is arranged 
in definite layers, which readily separate on sectionising. The individual cells are 
connected by distinct pits in the walls. These pits are seen everywhere in the 
ground tissue, and become more noticeable as the tissue increases in age. The 
collenchyma cells are much thickened, and towards the periphery become flattened 
and merge into the subepidermal phellogen. The cork cells become elongated 
radially and show marked foldings on the radial walls, probably due to the pressure 
exerted by the growth of the internal tissues. Deposits of tannin are found in the 
dead epidermis, and particularly around the bases of the silicified hairs. Lenticels 
of the ordinary type are common. 
The floral axis exhibits the same structure anatomically as the ordinary stem. 
On approaching the thalamus, the normal vascular ring divides into about fourteen 
distinct bundles. The pedicel bears two small opposite leaf-like bracts. The first 
pair of sepals are also opposite and decussate with the bracts. The leaf-trace bundles 
of the latter are similar in structure to those described below for the ordinary leaves. 
On nearing the thalamus the cortical bundles bifurcate, and one branch divides 
again. At this stage two of the vascular bundles of the central cylinder jut out at 
two opposite points into the peripheral ring, becoming the median vascular cords 
of the first sepals. Anastomosis occurs between the contiguous members of the 
last division of the peripheral bundles on the flanks. The occurrence of these 
anastomoses in the peripheral ring is very irregular ; several may be seen in one 
axis, and none in another. When the first sepal is given off, it receives a median 
bundle from the central vascular ring, and two laterals from the peripheral, ring ; 
but, before entering the sepal, anastomosis takes place between the median and the 
lateral bundles, and between the lateral bundles themselves. Similar anastomoses 
occur at the points of origin of all sepals, petals, and stamens. The vascular cords 
supplying the carpels arise from the central stele only. They receive no strands 
from the peripheral ring. Every time a branch of a peripheral bundle passes out 
into a floral segment, the xylem and phloem, which were inversely orientated in the 
pedicel, become normally arranged by a revolution through an angle of 180°, while 
the sclerenchyma disappears from the peripheral bundles as they approach the 
thalamus. 
The mode of entry of the leaf-ttace bundles in C. fertilis is complicated. In 
the petiole, there may be five or seven bundles, one large median and one or 
two smaller laterals on each side. The laterals gradually decrease in number by 
joining the median or the extreme laterals, till there are, eventually, only three left. 
This is the condition found at the base of the petiole near its insertion on the axis. 
The vascular ring of the stem opens, and, as the leaves are opposite, two gaps 
occur at each node. The foliar gaps occur between the peripheral bundles. The 
median foliar bundle enters the central vascular system through the gap, and is 
accompanied by the vascular cords from the two axillary buds, which arrange them- 
