Spirogyra setiformis (Roth) Kütz.

new YORK
botanical
qARDEN

SPIR0G2RA S3TIF0BMIS, (ROTE) ZTZ. - Fresh-water Algae of the United
States page 18, February 1872. (Smithsonian contribution to
knowledge, 241).

Sp. saturate viridis, lubrica; articulis sterilibus diametro paizl-
lum brevioribus ad 1£ plo longioribus; articulis fructiferis
haud inflat is; fasciis 3-8, latis, dentat is, interdum nonni-
hil remotis, sed saepe arete dense conjunctis, nodisos; zygospor*
is globosis vel late ovalibus.

Diam. - .0035".

Syn. - S. setiformis, (BOTHO KUTZING.
garum, Sect. III. p. 246.

Hab. - In stagnis, prope Philadelphia*

RABEMORST, Flora Sur op. Al-

Deep green, slipery; sterile joints a little shorter to one and
a-balf times longer than broad; fertile Joints not inflated;spi-
ral filaments 3-8, broad, dentate, sometimes somewhat remote,
sometimes closely and densely conjoined, nodose; zygospores
globose or broadly oval.

REMARKS.-None of the descriptions which I have seen of this species
state the number of the spiral filaments, but the other characters
of the American form so agree with those of the European plant
that it is probable that this one does also. The plant is not
unoommon in the Heck, fruiting in the spring.

Pig. 3 a, pi. 15, represents part of a sterile filament of
this species; 3 b, portion of a pair of fertile filaments,both
magnified 125 diameters.

Fig 3. SPIROGYRA SETIFORMIS YX./S*

NEW YORK BOTANICAL GARDEN

02015574

02015574