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REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 17
and plurilocular sporangia are borne at the base of the peripheral filaments. In
Elachistea there are also paraphyses.
CHORDARIEÆ.—In this family the branching frond is filamentous, and consists of an
axis of longitudinal filaments and a peripheral series of short filaments, which are
given off at right angles to the axis. The sporangia are found amongst the peripheral
filaments, the unilocular are ovoidal, and the plurilocular arise from the
metamorphosis of the cells at the outer extremity of the peripheral filaments.
ASPEROCOCCEÆ.—The fronds of this family are the counterparts of those in the
Scytosiphoneæ, but the sporangia, instead of being superficial, are external and do
not cover the whole surface, but are found in spots. The spots contain paraphyses
and spherical unilocular sporangia.
RALFSIEÆ.—In this family, composed of very few species, the frond is in the form of a
crust, resembling a lichen. The fruit is found on the surface in spots, composed of
paraphyses and unicellular sporangia.
SPOROCHNEÆ.—Here the frond is a solid branching filament and the fruit is found in
spots on the surface. Each spot consists of a number of paraphyses, at the base of
which are either oval unilocular sporangia or plurilocular sporangia in the form of
short filaments, resembling the sporangia of Phyllitis.
LAMINARIEÆ.—The family which includes the devil’s aprons and sea-colander of our
coast. The fruit either forms long patches or more or less irregular spots along the
center of the frond. Unicellular sporangia only are known. The sporangia are
separated from one another by peculiar-shaped unicellular paraphyses, which are
expanded at the top so as to cover the sporangia.
OOSPOREÆ.—In the order Zoosporeæ the sexual reproduction consists in the direct
union of two zoospores, which form a zygospore. The two conjugating zoospores, or
gameten if we adopt De Bary’s nomenclature, are alike in structure, and it is
impossible to say which is male and which is female. In the Cutlerieæ, of which no
representative has as yet been found on our coast, we have algæ resembling the
Phæosporeæ in habit, but differing from them in that their reproduction is of a
higher grade. The Cutleriæ have both zoospores and antherozoids, or proper male
organs. The zoospores are large, and are born singly in cells, which are united in
eights into an oblong body. The antheridia borne on distinct individuals are also
oblong in shape, but, instead of being divided into eight cells, they are formed of a
much larger number of small cells, in each one of which an antherozoid is produced.
The antherozoids are small oval bodies, almost colorless, and provided with two
lateral cilia. In Cutleria collaris Reinke found that the zoospores after swimming
about for some time, lost their cilia and came to rest. While at rest the antherozoids
approached them, and he considered that the sexual union then took place. Here,
then, we find a clear distinction of the sexes such as is nowhere found in the
Zoosporeæ, and it is but a step higher to the Oosporeæ, in which we have a distinct
male S. Mis. 59——2