Allen—Spermatogenesis and Apogamy in Ferns. 21 
thirty-four and thirty-five are drawn on a smaller seale (1950 
diameters) than the rest of this series. At the right in figure 
thirty-four is a surface view of the slender beak—at the left, a 
cross section of the main nuclear mass. 
Occasionally at this stage, and more and more frequently in 
later stages, little masses coloring dark blue in the triple stain 
are seen scattered in the cytoplasm. Several of these are pres¬ 
ent in figure thirty-four. 
Figure thirty-five represents a somewhat later stage than the 
preceding. The blepharoplast appears at two points in the sec¬ 
tion, once at its widest place where it lies in contact with the 
nucleus and again below where the plane of the drawing passes 
through its anterior end. 
About this time, the posterior end of the nucleus also begins 
to grow out into a slender curved projection. Both anterior 
and posterior extremities of the nucleus continue to grow for 
some time. At this time, too, the cytoplasm begins to decrease 
in volume, shrinking in about the nucleus. 
Figure thirty-six shows a stage in which one and a half turns 
of the spiral have been formed. This stage corresponds to the 
one in Adiantum represented in figure sixteen. In both, the 
blepharoplast runs the full length of the nuclear spiral and in 
both, the anterior end has pushed out forming a projection of 
the cell-body. In both, the greater mass of cytoplasm is at the 
posterior end. 
The later stages of the development of the antherozoids in 
'Aspidium resemble in the main, those of Adiantum. In one 
respect, however, the older antherozoids are unlike those of 
Adiantum. The cytoplasm contains numerous rounded gran¬ 
ules which stain dark blue. These are probably starch grains. 
Figure thirty-seven shows the posterior part of a nearly mature 
antherozoid. The cytoplasm contains a large number of these 
starch granules. They vary considerably in size and shape. 
These granules are still present in the cytoplasm of the mature 
antherozoids. Similar starch granules have been noted by 
various authors for other ferns. 
Living prothallia were mounted in a drop of water and 
watched under the microscope. The mature antherozoids were 
