Chroococcus limneticus Lemmermann 1898d, p. 153 

 PI. 100, Figs. 4, 5 



A free-floating, spherical or ovate colony of 4-32 spherical cells 

 rather closely and evenly arranged, sometimes in groups of 2-4 cells 

 as a result of rapid cell division; individual cell sheath usually 

 indistinct and confluent with the hyaline, mucilaginous colonial 

 envelope; cell contents dull to bright blue-green, not conspicuously 

 granular; cells 6-12-22/x in diameter, without sheath. 



This is one of the most common of all planktonic species found 

 in our region. Its distribution in acid or soft water habitats suggests 

 a specificity similar to that of C. turgidus in the tychoplankton of 

 highly acid mediums. 



Euplankter. Found in many lakes, especially soft or semi-soft 

 water. Mich., Wis. 



Chroococcus limneticus var. carneus (Chod.) 

 Lemmermann 1904, p. 101 

 PL 100, Fig. 6 

 A variety differing from the typical by its smaller size and the 

 irregularity of cell distribution within the colonial envelope; cells 

 4-16 in number, 7-9^ in diameter without sheath. 

 Euplankter. Found in several lakes. Mich., Wis. 



Chroococcus limneticus var. distans G. M, Smith 1916, p. 481 



PI. 100, Fig. 8 

 A free-floating ovoid colony of 8-32 globose or hemispherical 

 cells, rather widely separated (or in widely separated groups of 

 individuals) within a hyaline,- homogeneous, gelatinous colonial 

 envelope; cell sheaths confluent with the colonial mucilage; cell con- 

 tents homogeneous, gray to light blue-green; cells 6-8/* in diameter. 

 Euplankter. Found in several soft water lakes. Mich., Wis. 



Chroococcus limneticus var. elegans G. M. Smith 1916, p. 619 



PI. 100, Fig. 11 

 A free-floating colony of ovoid cells which are circular in one view 

 but flattened when seen from the side; cells irregularly scattered in 

 a wide, gelatinous colonial envelope; cell contents bright blue-green 

 and non-granular; cells 18-22/t in diameter without sheaths, 20-26/x 

 in diameter including the sheath. 

 Euplanlcter. Mich., Wis. 



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