90 COMPARATIVE EMBRYOLOGY OF THE RUBIACEAE 
partition, have thin walls with somewhat thinner cytoplasm, but no 
intercellular spaces. The conductive tissue is readily recognized 
in the style proper by the smaller transverse diameters of its cells. 
The change from this thin-walled tissue to the thick-walled is 
quite abrupt and takes place at the level of the roof of the 
ovary. 
At the lower extremity of the style, at the point namely where 
it fuses with the basal partition, the conductive tissue suddenly ex- 
pands from being long and narrow, to short, irregular and isodia- 
metric. There is also an evident increase in the thickness of the 
cell-walls. The line of fusion which may be recognized easily in 
the young condition as represented in jig. I is now so irregular 
as to be of itself unobservable. This irregularity and confusion of 
cells appears to be due to the thickening and partial gelatiniza- 
tion of the cell-walls or more especially of the middle lamella, 
for one may notice in sections that irregular lines of separation oc- 
cur between the cells, thus indicating their loose relations. ' Such 
changes have been noted, also, by Capus (2) although according 
to him such changes are much more pronounced in the style and 
stigma So far as the writer's observation goes such pronounced 
changes do not occur in the upper portion of the style, although 
here the walls are a little thickened, and that they are on the 
more and more pronounced the deeper one penetrates the whole 
style. 
At this point of fusion, as described in the previous paragraph, 
the ovules, two in Diodia, three in Richardsonia, are inserted upon 
the edge of the basal partition. The epidermis above described 
a undergoing a thickening of its walls is continuous with the 
epidermis of the ovules, a description of which is necessary at this 
point, 
The ovule is, broadly speaking, anatropous, and possesses, in 
addition to the single integument characteristic of the gamopetalae, 
a second outgrowth, the origin of which has been elsewhere de- 
scribed (p. 5 3) asa secondary enlargement of the funicle, a sort of 
strophiole. A profile view of this organ, as seen in Diodia teres, i$ 
Xt fig. 1, and as seen in Rickardsonía in jig. 9. 
ure of this organ with which we are at present concerned 
und modification of the epidermis to form a special con- 
striking feat 
is the profo 
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