118 Suuth on Structure and Parasitism 
rather deeply-stained protoplasm, and large conspicuous nuclei. 
In the middle of the nectary, these cells extend quite to the 
bundle-ring, but on each side there is a rapid transition to the 
parenchyma of the carpellary walls. There is no special 
covering of epidermal cells over the nectary (Plate XV, 
Fig. 7). Externally, the gland appears as a small, rounded 
whitish swelling at the base of the ovary. The presence of 
this gland seems to have been overlooked by Chatin, for he 
characterizes the genus as one in which the ovary is unaccom- 
panied by an hypogynous gland. 
STRUCTURE AND DEVELOPMENT OF THE OVULE AND SEED. 
The mature seed, which is very small and light, is sur- 
rounded by a tough, leathery coat, whose flattened cells have 
thickened indurated walls. The seed itself consists of a mass 
of endosperm cells, packed with starch, and enclosing a small 
primitive embryo whose cells contain little or no starch. 
The embryo is undifferentiated into plumule, cotyledons or 
radicle. These seeds will not germinate in water, nor in a 
nutrient solution made from the bruised roots of the host. 
Koch states absolutely that the seeds of O. speciosa, O. ramosa, 
O. minor, O. Hedere must come in contact with’ the host-root 
if they are to germinate, and Meehan finds the same for 
A phylton. 
I have not yet worked out entirely the development of this 
seed from the young ovule, and between Figs. 2 and 3 (Plate 
XV), I have as yet no certain connecting links. Fig. 1 shows 
the first appearance of the macrospore-mother-cell in very 
young ovules. The ovule is here still orthotropous, and is a 
small conical upgrowth, covered with one layer of cubical 
cells and containing a large macrospore-mother-cell. Fig. 
2, shows an older ovule. The ovule has here turned 
through an angle of nearly go degrees. The macrospore- 
mother-cell has greatly elongated, and is surrounded by 
