The President's Address. By Dr. It. Braithwaite. 177 
the time of impregnation the stigma is covered with a slimy secretion, 
sometimes so profuse as to drip on the table beneath. 
The antherozoids escape from the antheridia by the cover-cell 
becoming detached, and the contents are pressed out ; these are the 
mother-cells of the antherozoids, which soon burst and allow them to 
escape ; they are active for 30-40 minutes, and as if by an exercise of 
will, use the most determined efforts to reach the archegonia, where 
they force their way through the mucilaginous pellet to gain the 
neck, some pass down the canal into the oosphere, make a way into it 
at a thinner point termed the receptive spot, combine with its contents 
and disappear, the oosphere is fertilized and becomes an oospore. 
The asexual generation or fern proper now commences its growth ; 
the oospore divides into two by a septum parallel to the axis of the 
canal, and each of these again by a transverse septum, this embryo is 
then prolonged by lateral growth into the foot, by which it draws 
nutriment from the prothallus, and from one end of this proceeds the 
root, from the other the first leaf, and these gradually increase until 
the perfect fern is formed and becomes an independent plant enduring 
for an indefinite number of years. 
The Bryophyta or Mosses form three natural divisions, the Bryiuae 
or true Mosses, Sphagninae or Peat-mosses, and Hepaticse or Liver- 
mosses, though the first two are commonly united. In these the 
sexual organs consist of antheridia and archegonia, but they are of 
simpler structure than in ferns, and it is the first generation from the 
spore which is asexual. 
In the Mosses the spore bursts and emits the tubular endospore, 
which by repeated branching forms a septate confervoid protonema, 
visible as a felted stratum on damp ground, and highly chlorophyllose ; 
from the lower cells of this by lateral budding sexual plants are 
produced, which develope leaves and eventually antheridia and arche- 
gonia. The antheridia are sausage-shaped bodies on a short pedicel, 
composed of a single layer of cells, thinner and more transparent at 
apex, and generally surrounded by filiform, jointed trichomes named 
paraphyses, and inclosed in bracts or floral leaves. The contents of 
these organs are the mother-cells of the antherozoids, which are 
somewhat clavate at the posterior end, spirally coiled and tapering in 
front to a fine point, where they have two long and very fine cilia. 
Hedwig, in 1782, figured these male organs discharging the pollen 
as he termed it. The archegonia are flask-shaped, tapering into a 
long trumpet-shaped style, and inclosing at base a central cell, the 
protoplasm of which forms the oosphere ; above this is the canal of 
the style, formed as in ferns by the breaking up of the axial cells and 
formation of mucilage, which forces open the four apical cells and 
makes a passage for the antherozoids. 
The fertile oospore enlarges by cell-division into an ovoid embryo 
which pushes its way into the tissue below the archegone, and also 
grows upward on a pedicel bearing at its apex the sporogone or 
