VASCULAR SYSTEMS OF FLORAL ORGANS. 169 
IV. VIOLACEÆ (Pl. XXIV.)—vırı. VIOLA TRICOLOR.— The 
peduncle of a Pansy has four large cords (1). These increase and 
form a complete circle, seen on a level through the basal ap- 
pendages of the sepals (2). They now throw off five large cords 
for the sepals (3, s.); the three posterior being given off rather 
earlier than the two anterior, z. e., on the same side as the cal- 
carate petal (3, p.). A section a little higher shows the five 
cords ramifying in the lobes of each sepal (4). The next section 
reveals a very unusual condition of things, for instead of the 
remaining cords closing up and forming a circle again, they pro- 
duce a sort of platform of interlacing tracheæ embedded in 
phloém (5). These then arrange themselves into a somewhat 
triangular mass with three small ones alternating with them (6). 
The “ corners ” rise up and supply the three placentas (7, pl.) ; the 
three latter (instead of running straight up the wall of the 
ovary as will be seen in Reseda) bifurcate (9, a), aud the branches 
run up beside the placentas, leaving a space devoid of cords (8, 
9, sp.). This allows the ovary to break into three valves; an 
impossibility in Mignonette, as in that plant the dorsal cords run 
up midway between the placentas and are connected by trans- 
verse cords. Figure 10 represents a general diagram showing 
the distribution of all the cords. 
V. RESEDACEE (Pl. XXIV.).—1x. REsEDA oporata.—There 
are about eight cords in a pedicel (1). These multiply, but in- 
stead of forming at first a complete ring, the vascular eylinder 
appears deeply indented (2). The object of this becomes clear 
in the next section, in thatitisa preparation for forming two very 
perfect circles of cords (3, 4). The outer one sends off twelve 
cords for the sepals. Each sepal has, besides its midrib, a branch 
from each of the forking intermediate cords; so that there are 
three cords in each sepal (as shown by the bracket, 4, s.). The 
corolla being so extremely atrophied, the petaline cords are not 
recognizable. The outer circular series now sends off cords for 
the numerous stamens ; while the cords of the inner circle com- 
bine to form six groups (5-7), three, the larger ones (pl.), supply 
the placentas, and three smaller form the dorsal cords (d.). The 
former send off horizontal branchesto meet the latter (8). Hence, 
not only are there no vacant spaces down the wall of the ovary 
as in Viola, where the ovary can split into three valves, but in 
Reseda it is prevented from doing so by the horizontal connecting- 
ring. It is compelled, therefore, to open only at the summit. 
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