618 Wolfe. — Cytological Studies on Nemalion. 
lization, as they have been observed by the writer, correspond to the 
account given by Wille (’ 94 ) with the following exception. This author 
states (p. 59, 1 . c.) : { Wenn der Spermakern sich der Verengung des 
Carpogoniums nahert, wandert der Eikern diesem entgegen.’ In the 
numerous preparations of this stage in the writer’s material, the male 
nucleus is present in the upper part of the carpogonium, while the female 
still occupies its usual position (Fig. 12). 
Soon after, however, the female passes into the upper part of the 
cell, and there fusion takes place (Figs. ]3-i5). The male nucleus is 
often somewhat smaller than the female, although more frequently it is 
very nearly of the same size. Differences in staining power, such as 
were noted by Wille, were not observed. The staining of the protoplasm, 
according to the method employed to demonstrate these stages, somewhat 
veiled the processes, rendering an accurate examination of the finer 
details in fusion of the chromatic masses unsatisfactory. Actual fusion 
is evidently a very rapid process. In the scores of cases examined, no 
stages intermediate between these presented in Figs. 13 and 16 were 
observed. 
Just about the time of fusion, the protoplasm of the trichogyne 
separates from that of the carpogonium (Figs. 13-16). No cellulose plug 
appears to be formed, as stated by the earlier observers, but a distinct 
wall is thrown around the zygote within the original wall of the carpogenic 
cell, in much the same manner as has been described for the fertilized 
egg-cell of the Bryophytes. This wall, however, does not sever the 
original protoplasmic connexion with the cell immediately below (Figs. 
17 and 20), which Oltmanns (’ 98 ) has characterized as the hypogynous 
cell ; and soon after it is laid down, the fusion-nucleus passes from its 
position in the upper portion of the carpogonium to its normal one below 
the chromatophore. These characteristic positions of the nuclei are of 
importance, since they eliminate all possibility of mistaking late stages 
of zygote-division for fusion. 
As seen in Fig. 16, many spermatia may conjugate with the same 
trichogyne. Sperm-nuclei in all stages of dissolution can be noted at 
different points in this organ. Nuclei thus discharged appear to dis- 
integrate almost immediately. The protoplasm of the trichogyne contracts 
away from the delicate wall soon after fertilization, and the structure 
as a whole withers very rapidly. Small bodies resembling male nuclei 
(Fig. 14) were noted in several cases, indicating, perhaps, that more 
than one male nucleus may enter the carpogonium. This is, of course, 
not impossible, since the protoplasmic passage between the egg and 
the trichogyne is not broken until fusion is practically complete. Further 
information, however, concerning the origin and fate of these bodies was 
not obtained. 
