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1925 J Setchell-Gardner: Melanophyceae 421
9. Ectocarpus terminalis Kurtz.
Fronds 0.75-2 (or 4) nun. high, mostly forming a continuous
velvety layer, brownish in color; creeping filaments irregular,
branched, anastomosing and forming, at times, a partially pseudo-
parenchymatous layer ;
erect filaments simple or sparingly branched,
more or less attenuated above; cells of creeping filaments 8-24//. long,
lO-lfy/, broad ; cells of erect filaments cylindrical, 8-12//, broad, up to
six times as long; chromatophores short, band-shaped, few in each
cell; zoosporangia terminal, ellipsoidal, 26-52//. long, 20-30//. broad;
gametangia ovoid or ovoid-oblong, often curved, terminal, or lateral
and sessile or short-stalked, 48-120/* long, 16-32//. broad.
On larger Melanophyceae. Alaska (Unalaska) to southern Cali-
fornia (Laguna).
Kuetzing, Phyc. Germ., 1845, p. 236, Tab. Phyc, vol. 5, 1855, pi.
74, fig. Ill; Kjellman, Skand. Ectocarp., 1872, p. 54, pi. 2, figs, la, lb;
Setchell and Gardner, Alg. N.W. Amer., 1903, p. 237 ; Collins, Holden
and .Setchell, Phyc. Bor.-Amer. (Exsicc), no. 1034 (in part) (not
no. 1387).
We have accepted Kjellman 's interpretation of Kuetzing 's Ecto-
carpus terminalis and refer here, although not without some hesita-
tion, no. 1034 of the Phycotheca Boreali-Americana found growing
on stipes of Maria fistulosa in Unalaska Bay. There is intermingled
in our specimens, however, a plant which seems to be a form of
Ectocarpus confervoides. We have also referred here a plant found
growing on Fv.cus at Fort Ross, California.
The creeping filaments in this species anastomose more or less and
in some parts of the specimens form almost a parenchymatous basal
layer, strongly resembling that of the species of the Myrionemataceae.
Nearly every cell of the prostrate filaments gives off an erect filament,
a condition characteristic among the Myrionemataceae, but not gen-
eral among the Ectocarpaceae. The erect filaments are slender, with
rather long cylindrical cells, and bear terminal zoosporangia and either
terminal or lateral, sessile or short-stalked, gametangia. The chroma-
tophores are clearly band-shaped though short. No. 1387 of the
Phycotheca Boreali-Americana seems to be entirely made up of a
form of Ectocarpus confervoides.