WISCONSIN PHYTOPLANETON 39 



MICROCYSTIS FLOS-AQUAE (Wittrock) Kii'chner. PI. 5, Fig. 1. 

 in Engler & Prantl, D. nat. Pflanzenfam. 1 (Abt. la) : 56, fig. 49 N . 1900. 



Colonies spherical to ovoid, rarely elongate; frequently reaching a 

 macroscopic size. Cells compactly and evenly distributed within a very 

 delicate, hyaline, homogeneous, gelatinous envelope. Margins of colony 

 not sharply defined. Cell contents rarely homogeneous and grey to 

 pale blue-green; usually with pseudovacuoles and reddish in color. 

 Plant mass yellowish to verdigris-green. (Euplanktont). 



Diam. cells 3.5-6.5 /*. 



Bear (2) (rr), Big St. Germain (rr), Birch (1) (c), Birch Island (sss), 

 Browns (cc), Catfish (ss), Center (ss), Cochrane (sss), Duck (ss), Dunham 

 (rr), Fishtrap (rr), Pound (sss), Fowler (rr), High (rr), Horseshoe (1) (rr), 

 Kegonsa (cc), Loveless (r), Lower Nashotah (rr), Lower Nemahbin (r), 

 Mendota (aa), Mercer (rrr), Monona (aa), Mud (3) (cc), Nagawicka (rr), 

 No Mans (r), North Turtle (ss), Oconomowoc (ss), Paddock (ss), Palmer (ss), 

 Par dee (ss), Plum (ss), Pokegama (1) (ss), Rainbow (r), Rock (s), Rose 

 (ss), Sand (3) (r), .Shell (rr), Sishebogema (ss), South Turtle (ss), Squirrel 

 (rr), Star (ss), Tamarack (ss), Tenderfoot (rr), Upper Nashotah (rrr), Wapa- 

 gossett (ss), Waubesa (ss), Whitefish (ss), Winnebago (cc). 



MICROCYSTIS AERUGINOSA Kiitzing. PL 5, Figs. 2-3. 



Tabulae Fhycol. 1 : 6, pi. 8. 1845. 



Clathrocystis aeruginosa (Kiitzing) Henfrey, Trans. Micr. Soc. London N. S. 

 4: 53, pZ. 4, figs. 28-36. 1856 (in Quart. Jour. Micr. Sci. 4: 1856): Bachmann, 

 Arch. f. Hydrobiol. u. Planktonkde. 3: 61, figs. IV'-IV. 1908. 



Colonies spherical to subspherical when young, later becoming saccate 

 and ultimately reticulate and clathrate. Gelatinous envelope of colony 

 homogeneous, hyaline, and indistinct. Colonies frequently occurring 

 in sufficient quantity to color water a bright green. Cells spherical to 

 subspherical, evenly distributed throughout the colony and close to- 

 gether. Cell contents rarely homogeneous and grey to pale or bright 

 blue-green; usually with numerous pseudovacuoles and reddish. (Eu- 

 planktont). 



Diam. cells 3-4 p. 



Balsam (ss), Bear (3) (rr), Big Butternut (ss), Bloom (ccc), Bone (ss), 

 Browns (cc), Center (rr), Clam (r), Crooked (rrr), Delavan (sss), Desmoines 

 (ss), Devils (2) (rr), Duck (rr), Dutchmans (rrr), Eagle (ccc), Elizabeth 

 (cc), Fish (ss), Fowler (rr), Grassy (ss), Grindstone (rr), Half Moon (ss), 

 Hooker (ss), Horseshoe (1) (rr), Kawaguesaga (rr), Kegonsa (a), Kimball 

 (ss), Lac du Flambeau (rr), Lac la Belle (rr), Lake of the Woods (r), Little 

 Bass (2) (sss), Little Butternut (cc), Little Crooked (ss), Little Wood (ss), 

 Loveless (ss), Mendota (a), Meronk (ss), Mill (sss), Monona (cc), Mud (2) 

 (r), Mudhen (ss), Nancy (ss), Nicaboyne (ss), North Turtle (ss), North 

 Twin (cc), Oconomowoc (rrr), Old Taylors (r), Otter (rr), Owen (rrr), Par- 

 dee (ss), Pewaukee (ss), Pokegama (2) (rr), Pokegama (3) (ss), Prairie 



