NOTE 
DISCHARGE OF ANTHEROZOIDS IN FOSSOMBRONIA AND HAPLO- 
MITRIUM HOOKERI. — Campbell, 1 in describing the discharge of antherozoids in 
Porella Bolanderi Aust., states that the cells of the wall absorb water with great 
avidity, and finally the upper part bursts open by a number of irregular lobes, which 
curl back so strongly that many of the marginal cells become completely detached. 
According to Humphrey, 2 the method is similar in Fossombronia longiseta Aust. In 
1903, Cavers 8 pointed out in connexion with the explosive ejection of antherozoids in 
Fegatella Radd., that the mechanism of discharge was partly associated with the muci- 
laginous nature of the antheridial wall. This seems to be the case also in certain 
species of Fossombronia 4 recently described by the writer, and in Haplomitrium Hookeri . 
In both cases the discharge of antherozoids is preceded by a progressive series of 
changes in the wall of the antheridium. 
In Fossombronia , the antheridia arise singly between the base of the leaf and the 
stem, and are generally shut in by a little basal leaf-flap. When young they are pale 
green, and the contents can be seen through the wall. As the organ ripens, the 
chlorophyll granules of the wall-cells become orange coloured, and appear to become 
mucilaginous. The change in the chlorophyll corpuscles is progressively downward 
A, B. Fossombronia . C, Haplomitrium Hookeri. 
from the top of the antheridium. The corpuscles, in their final stage, are situated in 
the protoplasm close to the convex wall of the cell. They are of irregular shape, and 
are arranged in roughly parallel lines of granules or dentate rods, whose ends point 
toward the colourless concave side of the cell 
The wall of the antheridium shows differentiation into two forms of cells. Those 
Standing up from the base of the antheridium are three or four times longer than 
broad, the others are polygonal and of irregular outline. If the latter cells were 
removed, the former would make with the stalk a wineglass-looking object. As the 
antheridium develops the wall-cells become more* convex in outline, so that it has 
a warty appearance, and finally, on the point of dehiscence, it is difficult to convince 
oneself that the antheridium is not encased in tightly-fitting filaments. Dehiscence 
1 Mosses and Ferns, 1st ed., p. ior. 2 Annals of Botany, xx, 1906, p. 94. 
3 Annals of Botany, xvii, p. 274. 4 ‘ Observations on Fossombronia from Devonshire.’ 
[Annals of Botany, Vol. XXIII. No. LXXXIX. January, 1909.] 
