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482 University of California Publications in Botany [Vol.8
times as long, 11-13/a diam. at the apex, and 1-1.5 times as long, many
cells in the upper part of the filaments dividing 1-2 times longitudin-
ally ; ehromatophores band-shaped, few in a cell ; zoosporangia very
abundant, very variable in shape and size, narrowly ellipsoidal, clavate
to broadly ovoid, 40-130/x long, 20-35/* wide, sessile or on short pedicels
from the prostrate filaments, or lateral or terminal on the erect fila-
ments ;
gametangia rare, cylindrical, sessile or mostly short-pedicellate
on the creeping filaments, rarely terminal and tuberculate on the erect
filaments, 80-1 30/a long, 11-15/a broad.
Growing on the pneumatocyst of Nere&cystis Luetkeana, Neah
Bay, Washington.
Setchell and Gardner, Phyc. Cont. Ill, 1922, p. 357, pi. 36, figs. 3-8.
The unusual condition in Compsonema prevails in C. sporangi-
iferum. The gametangia seem to be of rare occurrence. Examination
of specimens of different sizes from different parts of the host revealed
the presence of a large number of zoosporangia in all stages of develop-
ment, many being empty. The gametangia are prevailingly near the
base, although occasionally a complex one appears terminal on an
erect filament. A very common character is the division of the cells
in the upper parts of the filaments into 2-4 parts by longitudinal walls,
producing a slight clavate condition in such filaments. We do not
know, at present, the morphological significance of this condition. The
zoosporangia and gametangia, so far as observed, develop on distinct
individuals.
13. Compsonema intricatum S. and G.
. Fronds 1.5-2.5 mm. high, more or less confluent, forming a con-
tinuous velvety stratum of indefinite expansion; creeping filaments
numerous, profusely branched, crooked; erect filaments numerous,
unbranched or with a few short branches near the base, straight, grad-
ually attenuated at the apices, piliferous in part ; true hairs absent
cells of creeping filaments irregular in shape and size ; cells of erect
filaments cylindrical, 8-9/* diam., 1-2.5 times as long, slightly narrower
at the base of the filaments; ehromatophores band-shaped; zoo-
sporangia ovoid to ellipsoidal, terminal on short filaments from the
creeping filaments or lateral and sessile or pedicellate on the erect
filaments near the base, 25-33/x long, 18-22/a broad ; gametangia ter-
minal on short erect filaments from the creeping filaments, lateral and
sessile or pedicellate near the base of the erect filaments or intercalary
in the main erect filaments, 80-12G> (up to 175/*) long, 10-14^ broad;
terminal and intercalary ones up to 60G> long ; loculi mostly 2-seriate.
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