VASCULAR SYSTEMS OF FLORAL ORGANS. 175 
minute and the whole of the tissue is so densely charged with 
chlorophyll, that they cannot readily be seen. Their positions 
are indicated by dots (4). 
Five carpellary cords arise in front of the petaline. Each 
of these, as also occurs in Erodium and Pelargonium, first divides 
into three (5, a): thus, the middle cord passes off as a dorsal 
carpellary (d.c.), while the other two portions of each of the 
original cords divide again (5, b); the two outer, which result 
from this last division, unite respectively with the adjacent por- 
tions of the nearest carpellary cords and stand between the 
placentary cords (6, 7.c.), and so form intermediate cords (5 b, i.c., 
and 6, 2.c.). The two inner portions (5 b, pl.c.) coalesce, as soon 
as the dorsal cord (55, d.c.) has passed off, and form the single 
placentary cord (6 and 7, pl.c.) in front of the ovary-cell. 
xvi. ERODIUM CICUTARIUM.— The peduncle of the umbel con- 
tains five cords (1), one being very small. This last is destined 
for tle bract. The other four increase in size and each becomes 
at first fan-shaped; then, by continuously branching, the outer- 
most tracheæ meet, and so a complete circle is formed (2). These 
supply the four pedicels (or else three, by the coalescence of two) 
of the umbels with their axial cylinders, each of which soon con- 
sists of five cords (3). 
The five cords of the pedicel increase and form aring. Ten 
cords are given off for the sepals; five of these bifurcate (4) so 
that the sepals receive three each (6, s.). The passage from 
fig. 4 to fig. 5 much resembles that from fig. 3 to fig. 4 in 
Geranium. The staminodes, however, have no cords (6, stde.). 
Figures 7, 8, and 9 represent sections below and at the base of 
an ovary-cell. In fig. 7 the euneate cord (5) has divided into 
three, one is passing off to become a dorsal cord (7, d.e.). Each 
of the remaining pair divides, as in Geranium; the two inner 
halves of the cords coalesce to form the placental cord (8, pl.). 
The other two unite with their nearest neighbours and form 
intermediate cords between the ovary-cells (8, 9, i.e.). These 
more or less lose their tracheæ and become sclerenchymatous in 
character. 
GERANIACEE (Pl. XXVI.).— Tribe Tropæoleæ. xvır. Pr- 
LARGONIUM ZONALE-— The pedicel has ten cords forming a 
perfect circle (1). As the base of the flower is approached, it 
spreads into a more elliptical form (2). As soon as the base of 
