shaped to hemispherical, lying either at the base of the cell or along 

 the lateral wall; pigment-spot lacking (?). Cells 2-3/^ in diameter, 

 3-5/x long. 



Rare to common in several lakes. Wis. 



Chlamijdomonas epiphytica G. M. Smith 1920, p. 91 



PI. 1, Figs. 6, 7 



Cells spherical to nearly pyriform, anteriorly narrowed into a 

 papilla-like beak. Cells becoming non-motile, adherent to the colon- 

 ial mucilage of Microcystis without losing flagella. Chloroplast a thin 

 parietal cup; pigment-spot lacking. Cells 7-8/x in diameter, 8-9/x 

 long. 



Common in several lakes. Wis. 



Chlamydomonas glohosa Snow 1903, p. 389 

 PI. 1, Figs. 8, 9 



Cells broadly ovoid to globose, inclosed in a hyaline, gelatinous 

 sheath; anterior papilla absent. Chloroplast a dense parietal cup 

 with a basal pyrenoid; 1 contractile vacuole in the anterior end of 

 cell; pigment-spot lens-shaped, supramedian in position and lateral. 

 Cells 5-7/x in diameter, 10-19/i, long. 



Tychoplankter; common. Mich., Wis. 



Chlamydomonas mucicola Schmidle 1897a, p. 17 

 PI. 46, Fig. 20 



Cells narrowly elliptic or narrowly ovoid, attenuated to a blunt 

 point anteriorly, broadly rounded posteriorly. Flagella II/2 times the 

 body in length. Chloroplast a lateral plate with a single large pyre- 

 noid; pigment spot and 4 contractile vacuoles in the anterior end. 

 Cells 3-4/x in diameter, 6-10/x long. 



Tychoplankter. Mich. 



Chlamydomonas polypyrenoideum Prescott 1944, p. 348 



PI. 1, Figs. 10, 11 



Cells ovoid to ellipsoid, without an apical papilla; gelatinous 

 sheath lacking (?). Chloroplast a dense parietal cup with a deep 

 median invagination; pyrenoids many (12-16), scattered; pigment- 

 spot not observed. Cells 8-10/a in diameter, 9-12/a long. 



Rare in euplankton. Wis. 



[71] 



