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IV. — The President's Address : On Reproduction in the Ferns 
and Bryophyta. 
By Robert Braithwaite, M.D., &c. 
(Read \lth February, 1892.) 
I have for the first time realized the difficulty I have heard expressed 
by my predecessors in this chair, viz. that of finding anything new 
as the subject for a discourse ; and I have come to the conclusion that 
the editors of your Journal are mainly responsible for this — they have 
become so Raptorial that it matters not in what country or in what 
language anything new in biological science is made known, it is also 
through the medium of your Journal at once disseminated through- 
out the English-reading world. 
What then is a poor President to do, unless he has abundance of 
time for original investigation ? Science marches so fast that there is 
danger of some of the old truths being forgotten, so I am going to 
recall to your minds some facts in the reproduction of Ferns and 
Mosses which are not new, but which, in my opinion, afford a striking 
example of what our noble instrument — the Microscope — has enabled 
us to accomplish in making clear some of the deepest secrets of 
nature, not only in the groups mentioned, but in all that has life. 
You all know something of the process of fertilization in flowering 
plants, how the anthers produce pollen, which at the proper time is 
shed on the prepared and moistened surface of the stigma, and how 
each pollen-grain throws out a fine tube which shoots down through 
the tissues of the style into the ovary, reaches an ovule, penetrates 
through the micropyle to the embryo-sac, and a spindle-shaped 
reproductive cell passes down this tube, divides into two, the anterior 
half enters the female cell, and the nuclei of the two become fused 
together, the ovule is impregnated, and developes into a seed capable 
of reproducing an individual like its parent. 
In the groups we are going to consider, this process much more 
closely resembles that in the higher animals, and, thanks to the 
Microscope, the union so far from being cryptic, is capable of being 
observed from beginning to end. I have brought these two subclasses 
together, because they have also other points in common, notably an 
alternation of generations, for in none of them does the spore produce 
a plant like its parent, but an intermediate growth, a sexual one in 
the ferns, bearing the reproductive organs which are absent from the 
perfect plant, an asexual one in the others, from which the sexual 
plant buds off and developes into the spore- producing moss. 
No doubt you have examined the beautiful ringed sporangium of 
a fern, which, when ruptured, gives exit to the dust-like spores; 
these bodies, when magnified, are seen to be subglobose and pyra- 
midal, the outer coat or exospore being a thickish, coloured, tuber- 
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