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112 ZYGNEMATACEAE
90. MoucEOTiA TROPICA (W. & G. S. Wcst) Transcau 1926. Ohio
Jour. Sci. 26, p. 325, PL 7, Fig. 112.
Vegetative cells 6-7/1 x 36-56/1; chromatophore with 2 pyrenoids;
zygospores unknown; aplanospores obliquely globose with projecting
mammillate solid processes, wall yellow-brown, scrobiculate, 27-28/1 x
27-29/1, with the processes 42-46/1 in length. (PI. XIX, Fig. 21.)
Africa, Angola.
91. MouGEOTiA MiAMiANA Transcau 1934. Trans. Amer. Micros.
Soc. 53, p. 222, PL 19, Figs. 41-42.
Vegetative cells 6-^.1 ti x 60-130/1; chromatophores with 2-6 pyre-
noids; zygospores unknown; aplanospores formed in the middle of
straight or slightly angled cells; outer sporangium wall covered at all
stages by a pectic layer; aplanospores globose to ovoid to ellipsoid with
projections at either end; globose spores 18-20/t in diameter, ellipsoid
spores 16-18/1 x 25-32/1; spore wall yellow, punctate. (PI. XIX, Figs.
22-23.)
United States: Oklahoma, Miami, August 14, 1932 (Taft Coll.).
92. MouGEOTiA VENTRicosA (Wittrock) CoUins 1912. Tufts Col-
lege Studies. 3, p. 76.
Vegetative cells 6-9/1 x 100-140 /i; chromatophores with about 4
pyrenoids in a single row; zygospores unknown; aplanospores obliquely
ellipsoid to subglobose, 12-24/1 x 16-29/1; spore wall smooth, yellowbrown.
(PI. XIX, Fig. 24.)
United States: Reported from California, Michigan, and Pennsylvania.
Have seen no specimens.
Sweden; Latvia.
93. MouGEOTiA PRONA Transcau 1926. Ohio Jour. Set. 26, p. 326,
PL 7, Figs. 109-11. .
Vegetative cells 8-12/1 x 60-1 40 (-280) /i; chromatophores 2 with
the nucleus between, pyrenoids 4-6 in each; zygospores unknown;
aplanospores obliquely ellipsoid with ends produced and truncate,
20-24/1 X 5o-52(-6o) /i; spore wall faintly yellow, punctate, with
rounded or retuse ends. (PI. XIX, Figs. 26-28.)
United States: New York, High Hill, Long Island, growing in a road-
side spring.
During the formation of an aplanospore an enlargement of the middle
portion of the cell develops. Simultaneously the protoplast begins to con-
tract and the 2 chromatophores move into the enlargement, i on each side
of the nucleus. The contracted protoplast is cut off from the 2 narrow parts
of the sporogenous cell by cross walls. A little later the spore wall develops.
Similar stages have been seen in other species of Mougcotia.