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44
ZYGNEMATACEAE
irregular in form and diameter, i. 8-6.5 /x, 1-8-7.2^ apart, brown at
maturity. (PI. VII, Fig. 15.)
China, rice fields, Tong-Kau, North Kwangtung, March 20, 1942.
Should be near Number 61.
93. Zygnema ellipsoideum Jao 1947. Bot. Bull. Acad. Stnica. 1,
p. 97.
Vegetative cells 20-22 ju. x 25-40 /n; conjugation unknown; aplan-
ospores ellipsoid, with somewhat pointed ends, 15-20^ x 22-25 (-30) m;
median spore wall yellow-brown, scrobiculate; sporiferous cells cylin-
dric, or somewhat inflated on one side.
China, Kwangsi, Suijen, May 31, 1938; fairly common in rice fields.
This is the first species with ellipsoid spores to be described.
Fig. a.—Zygnema etlipsoideuni aplanospores and sporangia. Figs. B. and C.
Zygnema mirificnm aplanospores, immature and mature. Both figures after Jao.
94. Zygnema mirificum Jao 1947. Bot. Bull. Acad. Sinica. 1, p. 97.
Vegetative cells i5-i8iu, x 25-63 /a; conjugation unknown; outer
aplanospore wall similar in shape and just inside the dolioform sporangium
wall, 22-30 /J. x 30-60 /A the median wall varies from ellipsoid to
ovoid in the bulge of the outer wall, 20-30 m x 25-30 ju.. The space between
the 2 walls is filled with yellowish colloidal material. The
median wall is irregularly and minutely scrobiculate, yellow-brown in
color.
China, Kwangsi, Suijen, June 17, 1938; in rice fields, very common.
This is a new type of 7,ygnema spore, with a colloidal layer between the
outer and median walls, and the 2 walls not of the same form. It is probable,
however, that the "granulose" surfaces of the median walls of certain other
species result from the coagulation of a preceding colloidal layer.
95. Zygnema khannae Skuja 1949. Nova Acta Soc. Sci. Upsali.
Ser. 4, 14, p. 99. PI. 22, Figs. 6-7.
Vegetative cells 24-28/1 x 30-70/1, conjugation unknown; reproduc-