DIODIA TERES 53 
of the basal partition. Quite soon the strophiole appears on the 
concave side of.the funicle )۸ 72, fig. 74), and the ridge grad- 
ually extends to the opposite side. With further development the 
micropyle becomes entirely closed by the strophiole, which agrees 
with its homologue in Diodia Virginiana in being possessed of 
special excretory cells containing raphides in large numbers, and in 
being the organ in which the vascular tissue of the ovule is dis- 
tributed. The cells adjacent to the vascular tissue are small and 
are more densely filled with plasma, and increase in size in ap- 
proaching the integument. The latter is not delimited from the 
strophiole by means of the brown cells which have been seen in 
D. Virginiana, and which are absent from the ovule entirely. The 
epidermal covering of the funicle and part of the strophiole is 
strikingly developed, and has been described more fully in another 
part of this paper. It is sufficient at present to point out the fact 
that they are deep columnar cells with thickened walls, and form 
a collar of tissue about the funicle, but having no relation to the 
nutrition of the ovule (pl. 73, figs. I, 7, 8). 
THE ARCHESPORIUM AND EMBRYO-SAC 
The archesporium is in all respects similar to that of Diodia 
Virginiana (pl. 12, fig. 15). Only one functional megaspore 
mother-cell is present which divides to form four megaspores (fl. 
12, figs. 16,17). One of these, probably the basal, judging from 
appearances, such as are seen, for example, in p/. 73, fig. 2, is the 
embryo-sac cell. This grows rapidly, becomes loaded with 
starch, and commences its migration along the micropylar canal. 
As the nucleus passes forward, a vacuole is formed behind it. 
This vacuole is.also present in Diodia Virginiana (pl. 12, figs. 2, 
4, and 5). 
The embryo-sac when mature is comparatively short, and only 
three antipodals are present, and we notice that, although one of 
these is much larger than the others, it is nevertheless much re- 
duced in length as compared with that cell in the forms previously 
described. The persistence of these cells for a considerable 
period, together with their heavy starch contents indicate that they 
have a considerable amount of activity. The functional activity 
of the antipodal cells even in this form where, to all appearances, 
