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EDGAR NELSON TRANSEAU 
the greater number of chromatophores, by the longer cells as compared 
with the width, by the smaller dimensions throughout, and the 
smooth median wells of the zygosj^ores. From S. majuscula Kuetz. it 
is readily separated by the larger dimensions, number of chromato- 
phores, and usually the greater curvature of the chromatophores. 
During some seasons this alga begins to fruit in May and continues to 
fruit until September. In other years spore formation extends from 
July to November, Thus far it has been recorded only from the 
East Big Four pond, three miles east of Charleston, and a "cut off" 
from Polecat creek, south of Ashmore. Type in herb. E. N. T. 
Collections No. 233, 246; 1461, 1647. Plate XXVII, figures 3-4. 
Spirogyra illtnoiensis nov. sp. 
Filamentis in caespites sordide virides et intricatos consociatis; 
cellulis vegetativis 65-85 latis, diametro 1.5-4-plo longioribus; 
chromatophoris 6-9, angustis, modo subrectis longitudinalibus, modo 
spiralibus, anfractibus .1-1; cellulis conjugatis abbreviatis, paulo 
inflatis et geniculatis, canalis conjugationis brevis et latis; cellulis 
masculis brevioribus quam femineis; zygosporis 85-115 /x diam., 
140-190 jLt longis, ovato-ellipticis vel ellipticis, mesosporio crasso et 
punctato, maturitate flavescentibus. 
Filaments forming dull green tangled masses; vegetative cells 
65-85 M X 100-300 m; chromatophores 6-9, narrow, nearly straight 
and longitudinal, or spiral, making from .1-1 turn in the cell; con- 
jugating cells shortened, somewhat inflated and geniculate, conjugating 
tube short and broad; male cell shorter than the female; zygospores 
85-115 iu X 140-190 /X, ovoid-elliptical to elliptical in form, median 
spore wall thick and punctate, yellow when mature. 
Evidently related to S. stictica (Eng. Bot.) Wille, from which it is 
distinguished by the larger dimensions throughout, greater number of 
chromatophores, and the punctate walled spores. From S. ceylanica 
Wittr. it differs in the number of chromatophores, and the markings 
of the spore wall. Conjugation is initiated by the bending of the 
gametangia and the development of slight prominences on both cells. 
This is followed by a mucilaginous secretion at the point of contact, 
which may persist as a ring about the tube for some days after the 
union of the cells is complete. After, contact the chromatophores 
of the gametangia become greatly enlarged and engorged with starch 
and fatty bodies, enlargement of the cells continues, but stops in the 
case of the male cell when the male gamete passes over. 
This species has been found only in the pond on the Gray farm, 
