Nov., 1915] Notes on the Zygnemales 23 



2-6 diameters long. The Vancouver specimens are producing 

 both aplanospores (globose, 24-26/x in diam.), and zygospores 

 (ovoid 24-28m x 36-44/i) by the union of gametes through the 

 partition wall separating the two gametangia. The specimens 

 show some evidences of being in an abnormal condition. 



SPIROGYRA Link. 



S. Juergensii Ktitzing. 



The specimen in P. B.-A. No. 510 from Knightsville, R. I., 

 distributed under the name of 5. longata (Vauch) Kiitz. with 

 cell diameter 27-30/i, and ellipsoid spores 30-33)U in diameter, 

 fertile cells enlarged, evidently belongs to this species. The 

 spores of 6". longata are distinctly ovoid with rounded ends. 

 In the Illinois specimens the spores of 5. Juergensii frequently 

 occur with diameters up to 33/x. 



S. varians (Hass.) Kiitz. 



The varieties scrobiculata Stockman and minor Teodoresco 

 have not been reported from America. They both occur 

 rarely in Illinois. The latter I have also seen in material 

 collected by Mr. Charles Bullard, at Lynnfield, Mass. The 

 former is characterized by its scrobiculate spores, the latter by 

 its smaller dimensions throughout. In my herbarium 5". 

 varians scrobiculata is represented in Collections No. 1799, 

 and 1881; and S. varians minor in Collection No. 2951. 



S. Borgeana nov. sp. 



Cellulis vegetativis 30-35/i x 50-200/^, dissepimentis planis, 

 chromatophoris singulis anfractibus arctis 1.5-5; cellulis fracti- 

 feris altero latere inflatis, altero latere (in quo conjugatio 

 sequitur) rectis; zygosporis ellipticis, 33-40^i x 54-70/x, membrana 

 media flava, glabra. 



Vegetative cells 30-35^ x 50-200m, end walls plane, 1 chroma- 

 tophore making 1.5-5 turns; fertile cells inflated on the outer 

 side, straight on the conjugating side; zygospores ellipsoid 

 33-40/i x 54-70/1, median wall yellow, smooth. Type in herb. 

 E. N. T. Coll. No. 1883, 1890. Charleston, Illinois. 



This species bears some resemblance to a form of 6". varians 

 figured by Professor Borge.* It differs from his figure in 

 that the conjugating side of the fertile cells is not at all swollen, 



*Borge, O., Beitrage zur Algenflora von Schweden. 



