This species differs from others of the genus in the Oocystis-like 

 and Nephrocytiiim-hke shape of the cells, and the numerous disc-like 

 chromatophores ( rather than plates ) . 



In Sphagnum bog pools. Mich. 



TETRAGONIELLA Pascher 1930, p. 426 



Solitary, tetragonal cells, triangular in outline when seen from 

 one angle, the four lobes in two different planes and cruciately 

 arranged; wall thick, sculptured with shallow depressions between 

 reticulations which produce serrations at the cell margin, the de- 

 pressions arranged in linear series about the cell, the wall at the 

 apices of the lobes thickened and extended into short, sharp points; 

 cell contents highly vacuolate, with a parietal reticulum in which the 

 numerous disc-like chromatophores are arranged, and with leucosin 

 granules and rod-like bodies; reproduction by zoospores containing 

 2-5 chromatophores. 



Tetragoniella gigas Pascher 1930, p. 426 

 PI. 95, Figs. 12, 13 

 Characteristics as described for the genus; cells (30)-45-50ju, in 

 diameter. 



In shallow water of an acid bog. Mich. 



TRACHYCHLORON Pascher 1939, p. 504 



Cells solitary, ovate, ellipsoid, or citriform, rhomboid in end view; 

 wall with reticulate thickenings and intervening depressions, making 

 the margin of the cell serrate; chromatophores 1 to several, elongate 

 band-like or H-shaped bodies, parietal, often with a thickened 'basal' 

 portion from which lobes extend; pyrenoids present or absent; 

 leucosin, fat globules, and reddish oil bodies present; reproduction 

 by aplanospores and zoospores. 



Key to the Species 



Cells fusiform; chromatophores 2-3 (rarely 1) T. biconnicum 



Cells broadly ellipsoid; 1 chromatophore T. depauperatum 



Trachychloron biconicum Pascher 1939, p. 513 

 PI. 95, Fig. 5 

 Cells broadly fusiform, with bluntly rounded poles; wall sculptur- 

 ing usually prominent; chromatophores 2-3 or several plate-like 

 bodies; cells 8-10/i, in diameter, 16-20/x long. 

 In shallow water of an acid bog. Mich. 



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