PALMELLA Lyngbye 1819, p. 203 



A shapeless, gelatinous mass, containing many spherical cells with- 

 out any order of arrangement; individual cell sheaths usually dis- 

 tinct at first, becoming confluent with the colonial mucilage. Chloro- 

 plast cup-shaped or bell-shaped, with 1 pyrenoid. Plants aquatic or 

 terrestrial. 



Palmella mucosa Kuetzing 1843, p. 172 



PI. 3, Figs. 8, 9 



Plant mass densely green, forming gelatinous expansions on the 

 substrate; individual cell sheaths evident at first but becoming in- 

 distinct; chloroplast parietal, covering nearly the entire wall; cells 

 6-1 4/i, in diameter. 



On submerged logs, aquatic plants, and other substrates; frequent- 

 ly on wet rocks, on sides of aquaria, or on cement basins. Wis. 



SPHAEROCYSTIS Chodat 1897, p. 119 



A free-floating spherical colony of from 4 to 32 spherical cells, 

 evenly spaced near the periphery of a non-lamellate gelatinous en- 

 velope, sometimes with a sheath about each group of 4 cells within 

 the colony. Chloroplast cup-shaped and covering most of the wall, 

 containing 1 pyrenoid. 



Sphaerocystis Schroeteri Chodat 1897, p. 119 

 PI. 3, Figs. 6, 7 



Colony often including both undivided and recently divided cells 

 which form small spherical clusters within the colonial envelope. 

 Cells 6-20/A in diameter; colonies up to 500/x in diameter. 



This plant should be compared with Planktosphaeria gelatinosa. 



Widely distributed and common in a variety of lakes, both hard 

 and soft water. Mich., Wis. 



GLOEOCYSTIS Naegeh 1849, p. 65 



Cells spherical, sometimes sohtary, but usually grouped in colonies 

 of 4, 8, or many individuals inclosed by a colorless gelatinous en- 

 velope, which may be globose or somewhat amorphous, lamellate 

 or (rarely) homogeneous. Chloroplast parietal, cup-shaped, but 

 often covering the entire wall, obscured by numerous starch grains 

 or oil bodies; 1 pyrenoid. This genus should be compared with 

 Sphaerocystis and Planktosphaeria. 



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