To BOTANICAL GAZETTE [JULY 
to the Hautschicht of the central cell; the other free nucleus 
does not appear in the section. This is about the latest stage at 
which these free nuclei retain their normal structure. They 
_ very soon begin to go to pieces, and the protoplasm of the 
pollen tube at the same time begins to disorganize. It becomes 
more homogeneous and retains more tenaciously the safranin 
stain. The nucleoli and chromatin of the free nuclei become 
more or less broken up and collected into masses of different 
size, a process which we shall see corresponds exactly to what 
occurs in the nuclei of the jacket cells of the archegonium 
shortly before its final division. Concomitantly with the disor- 
ganization of the nuclei and cytoplasm of the pollen tube, there 
becomes evident in the cytoplasm of the central cell a number 
of bodies staining a deep red in safranin. They resemble exactly 
the plastin granules that we have seen to appear at the disor- 
ganization of the free nuclei, and that they are actually transferred 
from the latter into the central cell seems possible. ig. 28 isa 
central cell after the appearance of these granules. They are 
arranged in a circular manner at some distance from the nucleus, 
and it may be that this distribution is connected in some way 
with the concentric arrangement of the fibers. At the time of 
the appearance of the plastin granules in the protoplasm of the 
central cell, there seems to be a distinct connection at the base 
of the cell between its protoplasm and that of the disorganizing 
material beneath it. Hirase (’95) describes large bodies lying 
in the protoplasm of the central cell of Ginkgo between the 
nucleus and the blepharoplasts. Webber (’97) confirms this — 
and says that in addition to the two large bodies smaller masses of 
similar material were observed in other localities of the cell. 
He speaks of them as extra-nuclear nuclein. It is easy to com 
pare these bodies with those of Taxodium. They stain deeply — 
with safranin in both cases, the principal difference being that in 
Ginkgo they are generally fused into two large masses which © 
occupy a definite position in the cell. 
The disorganized mass of nuclei and protoplasm at the tip of 
the tube never completely disappears before fertilization, and it 
may appear in the tip of the archegonium above the protoplasm 
