Kirchneriella lunaris (Kirchner) Mobius. (R). 



Micractinium pusillum Fresenius. (R). Found only 

 a few times in the plankton of the Buffalo region 

 in 1928. 



Mougeotia sp. (R). In shallow water. 



Nephrocytium agardhianum Naegeli. (R). 



Oocystis borgei Snow. (C). Autospores forming in 

 September. 



Oocystis c rassa Wittrock. (C). Polar nodules often 

 visible only on old cells. 



C)ocystis elliptica W. West. (C). Might be includ- 

 ed with O. Borgei, though the latter does show 

 the differences pointed out by Miss Snow. 



Oocystis eremosphaeria G.M.Smith. (R). Plastids 

 numerous. Cells 24-38 microns broad, 42-46 

 microns long. 



Oocystis lacustr is Chodat. (C). 



Oocystis parva W. and G.S. West. (R). 



Oocystis solitaria Wittrock. (R). Perhaps should be 

 included under O. crassa . The range of vari- 

 ation in the forms encountered in Lake Erie 

 make it very difficult to definitely place some 

 of the members of this genus. 



Oedogonium sp. (T). 



Pandorina morum Bory. (C). In August reproduction 

 by micro -colonies was common. 



Pediastrum boryanum (Turpin) Meneghini. (C). 



Pediastrum duplex Meyen. (C). Widespread. 



Pediastrum simplex Meyen. (C). Widespread. 



Quadrigula chodati (Tanner -FuUman) G.M.Smith 



(R). 



Quadrigula lacustris (Chodat) G.M. Smith. (R). 

 Smaller than above and with a single pyrenoid. 



Quadrigula pfitzeri (S chroder) G . M . S mith . (R) . 

 Cells in characteristic tetrads. 



Scene desmus abundans (Kirchner) Chodat. (R). 

 Western part of the lake. 



Scenedesmus bi jugatus var. flexuosus Lemmermann. 

 (R). Colonies usually contained 32 cells, but 

 16 and 8 were sometimes found, as observed by 

 Miss Snow (1903). 



Scenedesmus quadricauda (Turpin) de Brebisson. 

 (R). Shallow areas. 



Sphaerocystis schroeteri Chodat. (A). Reproduction 

 by formation of micro -colonies frequent. A 

 maximum of about 300 per liter in midsummer. 



Spirogyra tenuissima (Hassal) Kiltzing. (R). Oc- 

 curred as solitary filaments. 



Spirogyra sp. (R). Found only relatively near 

 shore. 



S taurastrum floriferum W. and G.S. West. (R). 



Staurastrum gracile Ralfs. (A). Most common 



desmid in the plankton. Maximum apparently 



during July and August. 

 Staurastrum longiradiatum W. and G.S. West. (C). 



Accompanying above species. 

 S tigeoclonium tenue KUtzing. (R). Wanderer from 



the marginal zone. 

 Tetraspora lacustris Lemmermann. (R). Late 



summer. 

 Volvox globator (Linnaeus) Ehrenberg. (R). Near 



Cleveland in August. 

 Westella botryoides (W. West) de Wildeman. (R). 



Heterokontae 



Botryococcus braunii KUtzing. (C). Occasional 



swarms in the surface tow, but never abundant 



in the quantitative samples. 

 Stipitococcus sp. ?. (T). Found once on Zygnema. 



In appearance resembling figures for this genus 



in West and Fritsch (1927). 



Chrysophyceae 



Dinobryon bavaricum Imhof. (R). 



Dinobryon divergens Imhof. (C). 



Dinobryon stipitatum Stein. (C). The combined 

 species of Dinobryon reached 400 per liter at a 

 number of stations in August and increased in 

 September to 3, 000 per liter at stations 27 and 29. 



Mallomonas alpina Pascher and Ruttner. (R). 



Synura uvella Ehrenberg. (R). 



Bacillariales 



Amphiprora ornata Bailey. (R). 



Amphora ovalis K'dtzing. (R). 



Asterionella formosa Hassal. (A). 27, 000 per liter 

 at stations 37 and 38 in June. Decline in July 

 and August followed by an increase to 60, 000 

 per liter in September at some of the western 

 stations. Present in every sample in September. 



Cocconeis placentula Ehrenberg. (R). 



Cyclotella comta (Ehjrenberg) KUtzing. (C). In 

 centrifuged samples. 



Cyclotella meneghlnian a KUtzing. (R). In centri- 

 fuged samples. 



Cymatopleura elliptica (de Brebisson) W. Smith. (R). 



Cymatopleura solea (de Brebisson) W. Smith. (R), 

 In surface tows. 



Cymbella cistula (Hempr. ) Van Heurck. (R). 



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