386 
The Ohio Naturalist. 
[Vol. IX, No. 1, 
enlarged centrosome or blepharoplast is of exactly the same 
nature as the centrosomes at the spindle poles in the earlier 
divisions. In the antheridial cells of Marchantia, therefore, we 
have normal centrosomes appearing at each division from the 
very earliest stages through the great grandmother, grand¬ 
mother and mother cell stages preceding the formation of the 
spermatozoids and according to Van Hook .they are also present 
in the vegetative cells. 
The lack of prominent asters in the last division is no doubt 
due to the decrease in size of the cell with corresponding decrease 
in the amount of cytoplasm. There is not sufficient space or 
material in which an aster could be developed. 
It is needless to give further observations, for they would 
only be a repetition of the observations so thoroughly reported 
by Ikeno. In conclusion it is only necessary to repeat that 
anyone with proper perseverance may obtain preparations which 
will verify the results here given; and further it is evident that 
the blepharoplast of Marchantia is only a slightly modified 
centrosome which can be traced back through many cell gen¬ 
erations and which is probably present in all the cell divisions of 
the entire ontogeny. 
This study was completed at the Botanical Garden of the 
University of Zurich, and I desire here to express my thanks to 
the director, Professor Dr. Hans Schinz, for many favors shown 
me while working in his laboratory. 
LITERATURE. 
Ikeno, S. Die Spermatogenese von Marchantia poly- 
morpha. Beih. z. Bot. Centralbl. 15: 65-88, 1903. 
Ikeno, S. La formation des antherozoides chez les Hepa- 
tiques. Comptes Rendus de l’Acad. des Sci. 136: 628—629, 1903. 
Ikeno, S. Blepharoplasten im Pflanzenreich. Biol. Centralbl. 
24: 211-221. 1904. 
Miyake, K. On the Centrosome of Hepaticeae. Bot. Mag. 
19: 98-101. 1905. 
Van Hook, J. M. Notes on the Division of the Cell and 
Nucleus in Liverworts. Bot. Gaz. 30: 394-399. 1900. 
Ikeno, S. Are the Centrosomes in the Antheridial Cells of 
Marchantia polvmorpha Imaginary? Bot. Mag. 19: 111-113. 
1905. 
Escoyez, E. Blepharoplaste et centrosome dans le March¬ 
antia polvmorpha. La Cellule 24: 247-256, 1907. 
Schottlander, P. Beitrage zur Kenntniss des Zellkems und 
der Sexualzellen bei Kryptogamen. Cohn’s Beitr. zur Biol, der 
Pflanzen 6: 267-304. 1892. 
Be’lajeff, W. Ueber die Centrosome in den spermatogenen 
Zellen. Ber. d. Deutsch. Bot. Gesells. 17: 199-205. 1899. 
