Mottier. — Development of the Spermatozoid in Chara. 253 
cilia. The nucleus occupies the middle part of the spermatozoid, while the 
blepharoplast extends its entire length. The anterior end of the blepharo- 
plast is thinner than the posterior. The two cilia are borne some distance 
back of the anterior end. The posterior portion is thicker, and usually ends 
bluntly. In cross section the blepharoplast is crescentic, being convex on 
the outside and concave within. It is of a homogeneous structure, except- 
ing a strip of granular substance along the concave side of the posterior 
end. The entire spermatozoid, as far as I was able to observe, makes two 
and one-half or three turns in a spiral. 
The blepharoplast arises as a delicate thread-like differentiation of the 
cytoplasm at the surface of the cell, extending some distance along the cell 
from the nucleus and on opposite sides of the latter. Whether the terminal 
portions of this thread extending from the nucleus originate as a single 
piece, or as two pieces, could not be determined with certainty in the 
earliest stages, but, later, the blepharoplast is clearly seen to be one piece, 
extending the entire length of the sperm. The blepharoplast seems to 
be a modification of the plasma-membrane, i. e. it did not seem to be 
formed within or without this membrane, but as a direct transformation 
of it that increased in thickness inwardly. No centrosome-like body, or 
4 Plasmahocker/ was observed from which the cilia develop, as described by 
Belajeff, Strasburger and others. The nucleus is transformed from an 
elliptical or oval body, with a hollow chromatin spirem, to a dense, homo- 
geneous, sausage-shaped structure making one or more spiral turns. The 
cilia were always found attached some distance back of the anterior 
extremity of the blepharoplast. They did not seem to grow at the expense 
of a protuberance or centrosome-like body. 
Literature Cited. 
Belajeff, W., 1894 : Ueber Bau und Entwickelung der Spermatozoiden der Pflanzen. Flora 
1-48, 1894. 
Van Hook, J. M., 1900 : Notes on the Division of the Cell and Nucleus in Liverworts. Bot. Gaz., 
xxx, 394-399* I 9°°- 
Ikeno, S., 1903 : Beitrage zur Kenntnis der pflanzlichen Spermatogenese : Die Spermatogenese von 
Marchantia folymorpha. Beihefte zum Bot. Centralblatt, xv, 65-88, 1903. 
Mottier, D. M., 1898 : The Centrosome in Marchantia. Proc. Indiana Acad. Sci., 1898. 
Strasburger, E., 1892 : Histologische Beitrage, iv, 107, 1892. 
