250 Mottier . — Development of the Spermatozoid in Char a. 
embraced largely by the nuclear portion of the spermatozoid (Figs. 9, 11, 
13). The blepharoplast is of a uniformly homogeneous structure, staining 
well with gentian violet of the triple stain. Along the concave side of the 
posterior end is the conspicuous row of granules mentioned in a preceding 
paragraph. These granules stain densely, appearing almost black in 
preparations otherwise well stained to bring out the remaining parts 
distinctly. Fig. 10 a and b represent two spermogenous cells as seen from 
the side (in lateral view) at the stage of development shown in Fig. 9 : 
a represents the sperm as seen from the surface, while b is an optical 
section. The dots on the right and left of the body of the sperm represent 
cross-sections of the cilia. In b , it is seen that the nucleus is cylindrical, 
being circular in section. The cytoplasmic mass is strongly concave on 
the side opposite the nucleus. In this concavity are shown two crescents 
which are sections of the ends of the blepharoplast. The larger crescent, 
above in the figure, is a section of the posterior end, and the lower that of 
the anterior end. From optical sections it is clearly seen that the 
blepharoplast is a band with the outer surface convex and the inner surface 
somewhat concave. The section of the blepharoplast at the left of the 
nucleus shows that the cilia-bearing band is closely applied to the nuclear 
membrane at the place of contact. The cilia are relatively very long, and 
lie rather loosely coiled in the spermogenous cell. Sometimes they seem 
to lie in contact with each other for certain distances (Fig. 14). In the 
final stages of the development of the spermatozoid the general cytoplasmic 
portion seems to be reduced to a mere vestige. - 
Unfortunately material was not available at the time of my study to 
enable me to fix the living spermatozoids upon the slide, and to stain them 
in that condition. This I hope to be able to accomplish sometime in the 
near future. 
In discussing the probable relation of the blepharoplast in Chara and 
in some of the lower Archegoniates, the observations recently published by 
Ikeno (’ 03 ) upon spermatogenesis in Marchantia polymorpha are of special 
interest. His excellent paper is the most thorough and complete account 
thus far given for any Liverwort. Only those who have attempted cyto- 
logical work in these plants can fully realize the difficulties encountered, 
because of the small size of the spermogenous cells, and the difficulty with 
which cytoplasmic structures, especially, are differentiated. 
Ikeno begins his study with the last two or three mitoses in the sper- 
mogenous tissue. In these mitoses he finds that centrosomes are present 
during certain stages, and that this structure functions finally as a cilia- 
bearer. 
In 1898 the writer (Mottier, ’ 98 ) called attention to the presence of 
centrosomes in the vegetative cells of the gametophyte of Marchantia 
polymorpha , and further study was made by Van Hook ( 1900 ) with similar 
