Download PDF

ZYGNEMA 25
thick, punctate, and markeci by an irregular network of ridges; pits
about iM in diameter, 3-6 /a apart. (Pi. II, Fig. 12.)
China, Hupeh, Wuchang (H. H. Chung Coll.).
11. Zygnema sinense Jao 1935. Sinensia. 6, p. 567, PI. i, Fig. 5.
Vegetative cells /i. 25-27 x 25-48 /i.; conjugation scalariform; spores
formed in the enlarged tubes, extending slightly into the gametangia;
zygospores subglobose to ovoid, not compressed, 35-42 /x x 40-48 /a;
median spore wall brown, pitted; pits 5-8 ^ in diameter, 3-9 /x apart.
(PI. Ill, Fig. I.)
China, Szechwan.
Differs from Z. lawtonianum Taft in larger zygospores, larger pits, and
absence of distinct suture; from Z. areolatum Transeau in having a single
median spore wall, larger pits, and smaller vegetative cells.
12. Zygnema globosum Czurda 1932. Susswasserfiora Mitteleuropa.
9, p. 109, Fig. no.
Vegetative cells 26-28^11 x ju.; 70-95 conjugation scalariform; zygospores
formed in the conjugating tubes, globose or ovoid, 45-50 m x
50-65 /x; median spore wall brown, thick, pitted; pits about 3/^^ in diam-
eter according to the figure. (PI. Ill, Figs. 2-3.)
Bohemia; Central India.
13. Zygnema adpectinatum Transeau 1934. Trans. Amer. Micros.
Soc. 53, p. 209, PI. 17, Fig. 6.
Vegetative cells 25-30 /^ x 30-1 00 ju,; conjugation scalariform; zygospores
formed in the conjugating tubes, ovoid to globose, 36-40 /x x
40-50 /a; median spore wall yellow-brown, scrobiculate; pits 2/^ in diam-
eter. (PI. Ill, Fig. 4.)
United States: Illinois.
14. Zygnema pseudopectinatum Czurda 1932. Susswasserfiora
Mitteleuropa. 9, p. 115, Fig. 117. Fritsch and Stephens.
Trans. Roy. Soc. S. Africa. 9, p. 53. 1921.
Vegetative cells 27-30 /a x 50-74 /a; conjugation scalariform and
lateral; zygospores formed in the conjugating tubes, globose to ovoid,
33-36 /x X 40M; median spore wall brown, thick, reticulate.
South Africa, Transkei.
15. Zygnema areolatum Taft & Transeau 1934. Trans. Amer.
Micros. Soc. 53, p. 210, PI. 17, Fig. 8.
Vegetative cells 27-30 m x 46-66 /x; conjugation scalariform; zygo-
spores formed in the conjugating tubes, globose to ovoid, 32-46^ x
33-50 ju; median spore wall brown, of 2 layers, of which the outer is