NEW SPECIES OF GREEN ALGAE 
291 
Spirogyra tenuissima (Hass.) Kuetz. var. rugosa nov. var. 
Cellulis vegetativis 11-13^ latis; zygosporis 28-32 X 55~64 /x, 
mesosporio subtiliter scrobiculato ; ceterum ut in typo. Cum vSpecie 
passim. 
Vegetative cells 1 1-13 jjl in diameter; zygospores 28-32 /jl X 55-64 fx, 
median spore wall minutely pitted, otherwise as in the type. Occur- 
ring with the species. 
This variety approaches the upper limits of the species in size, and 
is readily distinguished by its pitted median spore wall. It has 
been recorded from ponds at Charleston, Casey, and Lerna, a ditch at 
Dorans, and a small stream southwest of Wrightsville, Illinois. Type 
in herb. E. N. T. Collections No. 1871, 2270. 
Spirogyra inflata (Vauch.) Rab. var. foveolata nov. var. 
Cellulis vegetativis et fructiferis ut in typo, zygosporis mesosporio 
scrobiculato instructis. Cum specie passim. 
Vegetative cells and fertile cells as in the type, zygospores with 
median wall scrobiculate. Occurring with the species. 
This variety has been found in the Ice Plant pond, Casey, and 
in Campus Creek, Charleston, Illinois. It differs from the type only 
in the very distinct markings of the median spore wall. Type in 
herb. E. N. T. Collections No. 783, 784. 
Spirogyra rectangularis nov. sp. 
Filamentis plerumque sparsis; cellulis vegetativis 35-40 /x latis, 
4-9-plo longioribus, dissepimenta replicata; chromatophoris 2-4, 
anfractibus 2-5; cellulis fructiferis medio valde inflatis, quadraticis, 
48-70^1 latis; zygosporis ovatis vel cylindraceo-ovoideis, apice ro- 
tundatis, 45-65 fx latis, 75-120 ji longis; maturitate fuscescentibus. 
Filaments usually scattered ; vegetative cells 35-40 X 150-320^, 
dissepiments replicate; chromatophores 2-4, making 2-5 turns in the 
cell; fertile cells quadrately inflated toward the middle, 48-70 /x in 
diameter; zygospores ovoid to cylindrical-ovoid, with rounded ends, 
45~65 fjL X 75-120 fx; yellowish-brown at maturity. 
This species is related to S. quadrata (Hass.) Petit, which occurs in 
its typical form in an adjoining pond. It differs in its larger dimen- 
sions throughout, greater number of chromatophores, and the form of 
the zygospores. It has been found for several years in the West Tile 
Factory pond, Charleston, and a pond on the Gray farm southeast of 
Lerna, Illinois. Fruits during May. Type in herb. E. N. T. Col- 
lection No. 788. Plate XXV, figures 9-11. 
