Download PDF

104
ZYGNEMATACEAE
60. MoucEOTiA TRANSEAui Colliiis 1912. Tiifls College Studies.
Sci. Ser. 3, p. 77. Wittrock. Bih. Kgl. Svensk, Vetens}{.
Akad. Handl. 1, p. 39. 1872 (as M. tenuis).
Vegetative cells 9-13 /^ x 50-150 ja; chromatophore with 4-8 pyre-
noids in a single row; conjugation scalariform; zygospores globose to
triangular-ovoid, 20-30 /x x 26-36//., occupying the middle portion of the
receptive gametangium and the tube; spore wall yelknv, smooth; aplan-
ospores obliquely ovoid, 12-20/x x 20-32 /x, formed at the middle of a
straight or slightly angled cell which may be as long as the gametangium
or longer. (PI. XVII, Figs. 19-20.)
United States: Not uncommon from Oklahoma eastward to Massa-
chusetts and Florida.
England; Sweden; India.
The first of a series of 3 species in which the sporangium divides one of
the gametangia but not the other. In many collections of these species there
are filaments in which only part of the cells conjugate; the others form
aplanospores. Other collections contain only aplansporic filaments. Recently
Krieger has listed this species as M. abnorme Kisselev 1927. The figure in
Kisselev's publication of 1927 is probably of some other species, since the
first structures formed after conjugation are the 3 sporangial walls, and this
figure has no sporangial walls. The name M. tenuis Wittrock 1872 was
preoccupied by M. tenuis Kiitzing 1849, which proved to be a synonym of
M. scalaris Hassall 1842.
61. MouGEOTiA FLORiDANA Transeau 1934. Trans. Amer. Micros.
Soc. 53, p. 224.
Vegetative cells 14-20/x x 60-200 /a; chromatophores with 6-8 pyrc-
noids in a single row; conjugation scalariform; zygospores occupying
the middle of the receptive gametangia and the tubes, globose to trian-
gular-ovoid, i". 30-40 X 36-48 /a; spore wall yellow, smooth; aplanospores
obliquely ovoid, 18-24 /x x 30-45 m, occupying the middle part of the
cell; spore wall yellow, smooth.
Florida.
United States: Oklahoma and Texas eastward to Pennsylvania and
Northern India (Randhawa Coll.).
This species was collected by WoUe at Bethlehem, Pennsylvania, and
named M. tenuis (Cleve) Wittrock var. minor.
62. MouGEOTiA poiNciANA Transcau 1934. Trans. Amer. Micros.
Soc. 53, p. 224, Figs. 45-46.
Vegetative cells 21-25 ju, x 100-200 /it; chromatophores with 6-10
pyrenoids in a single row; conjugation scalariform; zygospores occupy-
ing the middle portion of the receptive gametangia and the tubes, tri-
angular-ovoid to globose, 36-44M X 35-51 /t; spore wall yellow, smooth;