422 Lawson . — The Gametophytes , Fertilization and 
perceptible changes. During the first week in June, however, when the 
tip of the tube with its contents has reached the depression just above 
the archegonium-complex, the nucleus of the body-cell prepares for 
division. It first enlarges slightly, the nucleolus disappears, and the 
chromatin loses its granular appearance and assumes the form of a coarse 
continuous thread, which winds irregularly through the karyolymph. 
A very careful study of the cytoplasm was made at this stage. Apart 
from the irregular distribution of the starch-grains, the cytoplasm surround- 
ing the nucleus appeared to be perfectly uniform. No differentiation that 
would suggest the presence of the blepharoplasts reported for Cycas 
(Ikeno, ’97), Zamia (Webber, ’97), and Ginkgo (Hirase, ’95) could be 
found. Coker (’03) has recently reported the presence of light areas 
at the poles of the cells in Taxodium , but he further states that the 
resemblance of these areas to blepharoplasts is 4 confined entirely to their 
position.’ It must be remembered that these centrosome-like structures 
have only been found where the male cell develops cilia, and that their 
function is confined to the organization of these motile organs. Where 
the pollen-tube acts as the carrier of the male cells to the archegonia, 
motile organs are no longer necessary. Cilia in connexion with the male 
cells of Coniferales have never been observed, and it is therefore not 
surprising that the structures responsible for their formation should also 
be missing. 
The stages showing the organization of the spindle which divides the 
body-cell were not found, but several sections showed the daughter-nuclei 
at the poles with the kinoplasmic fibrils between them. Fig. 5 shows 
a stage where the daughter-nuclei are completely organized, and the plate 
which divides the cell into two is forming at the equator. Several sections 
showing the development of the plate were examined, and it is apparently 
organized from the kinoplasmic fibrils which stretch between the daughter- 
nuclei. The daughter-nuclei now enlarge considerably, and each contains 
two or three nucleoli with the chromatin in the form of coarse granules 
suspended on threads of linin (Fig. 5 ). During the division of the nucleus, 
the body-cell loses its spherical form, and becomes more or less elliptical, 
as shown in Fig. 5 . 
Soon after its complete organization the cell-plate splits, and the two 
male cells are free and separate from each other. As shown in Fig. 6 , they 
are flat on one side and rounded on the other. They remain close together 
for some time, but when they separate they become spherical in form. 
The nucleus of each becomes very large, its diameter being about half the 
diameter of the cell. The chromatin is in the form of small, irregularly 
shaped granules suspended in a network of linin. The two male cells are 
of the same shape and of equal size, and, as we shall point out under the 
head of fertilization, they are both functional. 
