Cell Structure, Growth and Division in the Antheridia of Polytrichum etc. 123 
According to Vaillant (1863), the antheridium contains a mucous 
mass composed of transparent cells which result from the multiplication 
of the primitive elements of the tissue. The contents of each cell is finally 
organized into an antherozoid. 
Goebel (1882) says that in mosses, as in liverworts, each “mother 
cell” divides into two, each of which in turn forms an antherozoid. 
The interior cells of the antheridium of Funaria are found by 
Campbell (1895) to be strongly refringent in fresh material; in stained 
sections they appear much more granulär than the outer cells. 
Ikeno (1904) finds no centrosomes in the early mitoses in the an- 
theridia of Atrichum angustatum and Pogomtum rhopalophorum — a con- 
dition different from that which he (1903) describes for Marchantia. He 
suggests that centrosomes may originate during one of the later antheridia! 
divisions in the mosses. The chromosome number in the antheridia! cells 
of both species is eight. 
According to Arens (1907), the interior cells of the antheridia of 
Polytrichum juniperinum and Mnium hormm have a dense protoplasm. 
Each nueleus contains a large nucleole and little chromatin. In the pro- 
pliases of mitosis, the chromatin increases in amount, probably at the 
expensc of the dissolving nucleole. Eight chromosomes are present fbut 
according to Tischler’s (1908) review of this paper, Arens later finds 
six to be the correct number], The final cell division within the antheridium 
is diagonal, as in Marchantia and other liverworts. No centrosomes appear, 
but in the final division there is a blepharoplast at each spindle pole. The 
blepharoplast remains for a time near the daughter nueleus, then, after 
the daughter cell has rounded up, wanders to the cell periphery and takes 
part in the development of the antherozoid. 
W. and J. Docters van Leeuwen-Reijnvaan (1907 a — b) find that 
the resting nueleus of any antheridial cell (in Polytrichum piliferum, 
P. juniperinum and P. formosum ) contains only a large nucleole-like 
body, from which, preparatory to nuclear division, a smaller body is formed 
by constriction; the latter migrates into the cvtoplasm and there divides 
into two granules, which separate and pass to the positions of the future 
spindle poles. These “centrosomes” are not surrounded by radiations. 
In the reconstruction of the daughter nuclei, one centrosome is included 
in each. Similar processes are to be seen, though not so plainly, in cells 
outside the antheridium. The final division is not diagonal, as Arens 
maintains. The chromosome number in the antheridial cells, as in the 
vegetative cells of male and female gametophytes, is six. In each case, 
two of the six chromosomes are long, two of medium length and two 
