200 BOTANICAL GAZETTE [SEPTEMBER 
In nearly 5 per cent of the cases the rosettes were elongated to 
resemble suspensor cells. 
It will be seen that the third embryonal tube group, or fourth 
suspensor division, always consists of 2 or more cells, and after 
this division or the one following the tubes begin to elongate and 
interlock to form the suspensor. The transition from the jointed 
to the interlocked and more massive portion of the suspensor is well 
illustrated by figs. 47, 49, 50, and 51. 
The suspensor becomes more and more massive as the embryo 
increases in diameter. The embryo is first pushed as far as pos- 
sible into the corrosion cavity by the mechanical action of the 
suspensor; later it remains nearly stationary in the lower end of this 
cavity, but continues to give off the suspensor by the successive 
elongation of the cells from the radical end of the embryo; finally, 
as the embryo develops to its full size, the radical portion again 
reaches the archegonial end of the cavity. As the root cap becomes 
differentiated in the embryo, it may be seen that this organ and 
the suspensor gradually merge into each other; in fact, the late sus- 
pensor is formed from the root cap by the successive elongation of 
layer after layer of cells. 
ELONGATED CELLS.—The nuclei of the suspensor cells and 
embryonal tubes always seem to hold a definite size relation to the 
cells. A large suspensor tube may frequently contain a nucleus 
larger than an entire cell in the embryonal group at the apex. 
The position of these nuclei is always at the embryonal end of these 
tubes. More of the cytoplasm of the cell is usually found here, 
near the nuclei. The ends of these cells containing the nuclei are 
frequently enlarged considerably. Often one of the primary sus- 
pensor cells breaks loose at the lower end during elongation. Figs. 
41 and 45 show such tubes which continued to enlarge at the 
lower end and formed a balloon, while fig. 42 shows an earlier stage 
in another tube. These phenomena are not uncommon. 
BASAL PLATE.—A thickened plate (p) is deposited above the 
rosette soon after the suspensor begins to elongate. Something 
similar was found in Podocar pus, where CoKER (6) calls it a cellulose 
plug, “a novelty among gymnosperms.” It is called a “basal 
plate” by the writer because it is a plate rather than a plug, and its 
