WISCONSIN PHYTOPLANKTON 155 



var. major var. nov. PI. 39, fig. 11. 



Cells up to 9 n broad and 25 /* long. Spines 15 //, long. (Facultative 

 Planktont ?). 



Palmer (rr). 



SCENEDESMUS BRASILIENSIS Bohlin. PI. 39, Figs. 12-14. 

 Bih. Kgl. Sv. Vet.-Ak. Handl. 23, Afd. 3, No. 7: 22, pi. 1, figs. 36-37. 1897. 



Coenobia flat, of 2-4-8 (generally 4) cells arranged in a single linear 

 series. Cells cylindrical to ovoid-ellipsoid, with a single longitudinal 

 ridge extending from pole to pole on each side of the cell. Poles with 

 1-4 small teeth. (Facultative Planktont). 



Cells 3-6 ^ broad, 11-24 //. long. 4-celled coenobia 11-24 //, broad, 

 12-25 /* long. 



Bear (2) (r), Beaverdam (rrr), Chain (rrr), Clare (rrr), Deer (rrr), Jag 

 (rr), Lac du Flambeau (rrr), Lake of the Woods (rrr), Lindy (rr), Little 

 Doctor (rr), Old Taylors (rr), Pine (2) (rr), Rice (1) (rr), White Sand (rrr). 



The species may be distinguished from S. denticulatus by the linear 

 ridges on the sides of the cells. 



SCENEDESMUS HYSTRIX Lagerheim. PI. 39, Figs. 15-16. 

 o'fvers. Kgl. Vet.-Ak. Forh. 39, No. 2: 62, pi. 2, fig. 18. 1882. 



Coenobia flat, of 2^4-8 cells joined in a single linear series. Cells 

 oblong-cylindrical, with blunt conical apices. Entire surface of cells 

 covered with minute spines. (Tychoplanktont). 



Cells 3-5 p. broad, 8-18 /* long. 4-celled coenobia 8-18 /, broad, 12- 

 25 p. long. 



Rudolph (rrr). 



SCENEDESMUS DENTICULATUS Lagerheim. PI. 39, Figs. 17-19. 

 Ofvers. Kgl. Vet.-Ak. Forh. 39, No. 2: 61, pi. 2, figs. 13-17. 1882. 



Coenobia flat, generally four-celled. Cells ovoid to ovoid-ellipsoid, 

 arranged in a linear or subalternating series. Poles of cells without 

 ridges but with 1-4 short spines. (Facultative Planktont). 



Cells 5-11 /x broad, 7-15 /*, long. 4-celled coenobia 7-15 ju, broad, 

 15-22 /i long. 



Amicoy (rr), Bear (2) (rr), Browns (rr), Chain (rr), Deer (rrr), High (r), 

 Hillman (rr), Horse (rrr), Horseshoe (2) (rr), Lac du Flambeau (rrr), Lit- 

 tle Doctor (rrr), Silver (3) (rr), White Ash (rr), Wolf (rr). 



