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1925] Setchell-Gardner: Melanophyceae 483
Growing on Fhcux furcatus f. Carmel Bay, Monterey County,
California.
Setchell and Gardner, Phyc. Cont. Ill, 1922, p. 354, pi. 35, figs. 1-3.
Compsonema intricatum has diverged very far from a typical
Compsonema. The size of a single individual at maturity cannot be
ascertained, since 1 the creeping filaments, and to some extent the erect
filaments, are thoroughly and inextricably intertwined, forming con-
tinuous velvety strata on the surface of the host for several inches in
expanse. The gametangia have, to a considerable degree, moved to
the lateral position, the majority, however, remain terminal on long
pedicels from the basal filaments. The lateral position is characteris-
tic of Ectocarpus. The intercalary gametangia are typical of the
genus Pylaiella. The creeping filaments are very numerous, although
they do not radiate regularly side by side, thus forming a regular
circular disk typical of the genus Myrionema. The zoosporangia (?)
are numerous and develop with the gametangia on the same individual.
It is exceedingly doubtful whether or not these structures are func-
tional. At the stage in which the material was found, they were prac-
tically all of the same size, and some of the accompanying gametangia
were empty. There is no indication of the formation of zoospores.
They are filled with what seem to be densely crowded, angular chro-
matophores. The apical end is slightly beaked, and the outer wall
dissolved, except a thin inner membrane. Their position on the same
plants with gametangia, the peculiar open beak, and the fact that they
all seem to be of the same age lead us to suspect that they are some
sort of abnormalities, or pathological conditions of the gametangia,
which will require much more investigation to interpret. We have
retained this in the genus Compsonema on account of the prevailing
simplicity of the erect filaments and the abundance of creeping fila-
ments, practically every cell of which gives rise to an erect filament.
14. Compsonema secundum S. and G.
Plate 54, figs. 1, 2
Fronds very small, usually more or less confluent ; prostrate por-
tion monostromatic, composed of much crisped, branched filaments
cells of creeping filaments irregular in shape, 7-8/*, diam., variable in
length; erect filaments up to 1.25 mm. long, unbranched, or rarely with
a few short fructiferous ramuli ; cells of erect filaments cylindrical,
~k~)-6.7)/x diam. at the base, 4.5-6 times as long, 5). 5-10. 5^ diam., in
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