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POPULAR SCIENCE REVIEW. 
Dodel-Port’s paper, with figures, appears in u Nature ” of September 11. 
Like many other Floridese, Polysiphonia subulata is dioecious, and the male 
and female plants appear often to grow at a considerable distance apart. The 
antherozoids, which are produced from antheridia presenting a considerable 
external resemblance to microscopic ears of maize, are described as mere 
globules of protoplasm, containing a small highly refractive nodule and a few 
plasma granules, but entirely destitute of cell- wall, and consequently of the 
cilia, by means of which the antherozoids of so many Algse make their way 
through the water in search of the female organs which they are destined to 
fertilize. The antherozoid is thus precisely analogous to the pollen grain of 
an anemophilous phanerogamous plant. 
The female reproductive organ in this plant is a multicellular body forming 
an outgrowth from the apical parts of the branches of the thallus. The 
youngest of these carpogonia is found nearest the apex, those lower down 
being more mature. The structure of the carpogonium is described by 
Professor Dodel-Port in detail, but the most important point for our present 
purpose is the presence at its summit of two hair-like organs — a forked hair 
composed of several cells ; and a trichogyne, a slender, colourless, unicellular 
hair, a little shorter than the forked hair, and produced from the surface of the 
carpogonium at a later period, making its appearance, in fact, about the time 
when the unfertilized carpogonium arrives at maturity. When full grown 
it is of a cylindrical form, abruptly rounded off at the extremity, and its 
narrow interior canal is filled with colourless, finely granular protoplasm. 
The trichogyne is most important, as it is the receptive organ, analogous to 
the elongated style which occurs in so many phanerogams. Fresh anthero- 
zoids of Polysiphonia subulata on coming into contact with the upper part of 
the trichogyne, which seems to some extent to act as a stigma, immediately 
adhere to it firmly, when the granular contents of the antherozoid pass into' 
the interior of the trichogyne, and a part of them descending the canal in 
the latter reach the carpogonium, of which they fertilize the central cell. 
This process, as will be seen, is very analogous to that which takes place in 
phanerogamous plants. 
In the case of anemophilous or wind-fertilized dioecious plants it is well 
known that the chance of fertilization is usually greatly increased by the- 
enormous quantity of pollen which the male flowers yield to every passing 
breeze, and a similar provision is found to prevail in the case of the dioecious 
Polysiphonia. It is perfectly clear that the antherozoids of this plant, being 
quite destitute of any locomotive organs, must be passive in their further 
proceedings, and they are no doubt earned along in all directions by the 
currents, and other movements of the water, until, on meeting with the 
trichogyne of the female plant, they adhere to it, and fulfil their duty. 
When the two sexes grow at no very great distance apart, Professor Dodel- 
Port seems to think that the small marine animals, Crustacea, annelids, star- 
fish, infusoria, &c., which swarm in the submarine forests of Floridese, may 
aid importantly in effecting the transportation of the fertilizing element to 
the female organ, but in the course of his investigations, he discovered that 
certain minute animals interfere in the process in a much more curious and 
interesting fashion, vividly reminding us, indeed, in the singular adapta- 
tion of means to ends, of the wonderful relations unquestionably existing- 
