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ZYGNEMATACEAE
with concave sides, angles with hornUke processes; spores about 28/x
on a side. (PI. XVIII, Fig. 17.)
Austria, Karnten.
74. MouGEOTiA ELEGANTULA Wittrock 1 872. Om Gotland och
Oelands Sot. Alg., p. 40.
Vegetative cells 3.5-5 M x 50-1 35 /a; chromatophore with 4-8 pyre-
noids in a row; conjugating cells geniculate; conjugation scalar iform;
sporangium dividing both gametangia; zygospores cruciate-quadrate,
1 8-24 /J. X 18-24/', ^^^^^ rounded corners; spore wall hyaline, smooth;
aplanospores ellipsoid, 6-9/1 x 20-24/1, otherwise similar to the zygo-
spores. (PI. XVIII, Figs. 21-22.)
United States: Wisconsin; Iowa; Texas eastward to Massachusetts.
Widely distributed in Europe; China, Yunnan; West Indies.
At Twin Lakes, Michigan, a specimen was collected in which a zygo-
spore had been formed by scalariform conjugation between 2 cells of the
same filament, which had been bent into a loop.
75. MouGEOTiA BooDLEi (W. & G. S. Wcst) ColHns 1912. Tufts
College Studies. 3 (2), p. 76.
Vegetative cells 4-5.5 M x 25-225/1; chromatophore .5-8 of the
length of the cell, with 4-6 pyrenoids in a single row; reproduction
usually by aplanospores, very rarely by zygospores; conjugation scalariform;
zygospores quadrangular, 15-18/i x 15-23^, corners somewhat
rounded; aplanospores ellipsoid, 12-15/1 x 23-25 /i, projecting slightly
on the convex side of the slightly curved sporangia; spore wall yellow
to brown, punctate. (PI. XVIII, Figs. 23-25.)
United States: Illinois, Charleston; Oklahoma (Taft Coll.).
British Isles.
Very abundant for several years in a lily pond on the campus of the
Eastern Illinois State Teachers College at Charleston, Illinois; fruited there
both in the spring and autumn months. Among the hundreds of aplanospores
examined perhaps a total of 25-30 zygospores was found. The Oklahoma
specimens had spores darker than the Illinois specimens.
76. MouGEOTiA GRACiLLiMA (Hassall) Wittrock 1872. Bih. Kgl.
Svensk, Vetensk,. A\ad. Handl. 1, p. 40.
Vegetative cells 5-7 /t x 55-140/1; conjugation scalariform; sporan-
gia dividing both gametangia; zygospores quadrate, with deeply con-
cave sides, 20-25/1 X 20-28/1, angles refuse; spore wall minutely ver-
rucose; aplanospores spindle-shaped. (PI. XIX, Figs. 1-2,)
chusetts.
United States: Texas; Michigan; Illinois to New York and Massa-
Europe, generally distributed throughout.