plasts numerous, disc-like; paramylon bodies 2 to several long rods; 

 10-1 4/x, in diameter, 140-180/* long. 



This is a widely distributed but rather uncommon species. It is 

 almost at once identifiable by the narrow and very long, rigid cell. 



In Sphagnum bogs and swamps. Mich., Wis. 



Euglena acus var. rigida Huebner 1886, p. 9 

 PI. 85, Fig. 27 



Cell rigid, swimming slowly and continuously in one direction, 

 spindle-shaped but narrow and elongate, tapering abruptly poster- 

 iorly into a sharply pointed tail-piece; paramylon bodies in the form 

 of 2 long rods ( rarely more numerous small rods ) ; chloroplasts num- 

 erous, plate-like and ovoid bodies, sometimes showing a spiral 

 arrangement within the cell; 5.5-10/a in diameter, 118-125/x long. 



Uncommon; in ditches and among dense growths of algae in bays 

 of lakes. Wis. 



Euglena convoluta Korshikov 1941, p. 23 



[Euglena brevifiagellum Prescott & Gojdics] 



PI. 86, Figs. 7-9, 14 



Cells slightly metabolic, elongate-fusiform, and spirally twisted 

 or curved, seldom straight, elliptic in cross section, rather abruptly 

 narrowed anteriorly and truncate posteriorly, narrowing more grad- 

 ually to form a long tail-piece. Membrane finely and spirally striate. 

 Flagellum short, about one-sixth the length of the cell. Paramylon 

 bodies of two sorts: 6-8 large, concave or trough-shaped plates 

 laterally arranged, parallel with the long axis, witli the pellicle 

 slightly undulate over them; and numerous small disc-like rings 

 irregularly scattered throughout the cell. Chloroplasts numerous 

 ovoid discs evenly distributed throughout the cell; pyrenoids lacking 

 (?); eye-spot elliptic, composed of irregularly arranged crimson 

 granules. Cell 120-145/x long, 10-12/* in diameter; large paramylon 

 bodies 18/* long; small paramylon grains 5/* wide, 7/i long. 



This species is bent and spirally twisted but does not turn in its 

 forward movements, and thus appears to be quite rigid. It is, how- 

 ever, metabolic at times. Apparently the bending of the cell and 

 the undulations of the membrane are determined by the position 

 and junctions of the large lateral paramylon bodies. Upon contrac- 

 tion of the cell, the paramylon discs are seen to telescope laterally. 

 The striations of the membrane are extremely fine, sometimes almost 

 undiscernible. They spiral left to right, proceeding posteriorly. 



Tychoplankter; in Trilby Lake, Wisconsin. (Also reported by 

 Gojdics in a pond near Woods Hole, Massachusetts, August 1935. ) 



[391] 



