Trachelomonas crebea var. brevicollaris Prescott 



in Prescott, Silva, & Wade 1949, p. 89 



PL 84, Fig. 17 



Test ovate; flagellum aperture in a very short, ring-like collar; 



wall uniformly granular and roughened; test 2S-25tx in diameter, 



Sl-^Six long. 



The chief difference between this and the typical form is the 

 very short neck, reduced to a collar; other characteristics, such as 

 wall decoration and size, are similar to those of the typical form. 

 In a swamp near Boulder Junction, Wisconsin. 



Trachelomonas cylindrica Ehrenberg 1833, p. 315 



(Sec. Playfair); Deflandre 1926, p. 75 



'Pl. 83, Figs. 11, 20 



Test oblong-cylindric; broadly rounded at the posterior end but 



somewhat flattened anteriorly; wall smooth, yellowish; flagellum 



opening surrounded by a short collar; test 8-10/x in diameter, 



14.8-20/. long. 



In roadside swamps and ditches. Wis. 



Trachelomonas dubia ( Swir. ) Deflandre 1926, p. 106 



PI. 85, Figs. 1, 2 



Test cylindrical, broadly rounded posteriorly, truncate at the 



anterior end and abruptly narrowed to form a short cylindrical 



neck; wall smooth, thickened at the base of the collar; test 11— 14/. 



in diameter, 26-28/. long. 



Euplanktonic and tychoplanktonic. Wis. 



Trachelomonas Dybowskii Drezepolski 1922 

 ex Deflandre 1926, p. 70 

 PI. 83, Fig. 21; PI. 84, Fig. 6 

 Test broadly ellipsoidal to ovoid; flagellum opening without a 

 collar, sometimes with an inner thickening of the wall about the 

 aperture; wall smooth; test 10-18/. in diameter, 16-32/. long. 

 Euplanktonic and tychoplanktonic. Wis. 



Trachelomonas erecta Skvortzow 1925, p. 62 

 PI. 85, Fig. 16 

 Test cylindrical, broadly rounded both posteriorly and anteriorly; 

 flagellum aperture without a collar; wall coarsely and densely 

 punctate; test 15.6/i in diameter, 31.2/. long. 

 Tychoplankter. Wis. 



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