372 OHIO BIOLOGICAL SURVEY 



chloroleucites numerous, discoid; pyrenoids absent; paramylon in 

 the form of 1-2 elongate rods anterior and posterior or lateral to 

 the nucleus. 



Reproduction ( ?) . 



L. 82;u. D. 10;u. 



Distribution, Europe. 



*33. E. acutissima Lemm. (Fig. 10, PI. XIV). 



Elongately fusiform, rigid, with needle-like tip ; periplast 

 weakly striate spirally; flagellum short; chloroleucites numerous, 

 discoid, arranged in spiral lines: pyrenoids absent; paramylon in 

 the form of 2 elongate rods, one anterior, the other posterior to 

 the nucleus. 



Reproduction ( ?). 



L. 123/^. D. 7/x. 



Distribution, cosmopolitan. 



Ohio, Fremont. 



-34. E. spirogyra Ehrenb. (Fig. 1, PI. XV). 



Elongately cylindrical, narrowed anteriorly while posteriorly 

 produced into an acute tip often slightly bent into a crescentic 

 shape, slightly metabolic ; periplast yellowish brown with promi- 

 nent spiral punctuations, a prominent row often alternating with 

 a less prominent row; flagellum short; chloroleucites numerous, 

 discoid ; pyrenoids absent ; paramylon in the form of 2 prominent 

 annular granules, the one anterior, the other posterior to the 

 nucleus. 



Reproduction by longitudinal division and by cysts without 

 a gelatinous envelope. 



L. 80-150/1. D. 6-20/.. 



Distribution, cosmopolitan. 



Three varieties have been recognized, var. ahrupte-acuminata 

 Lemm., 125/x in length and 15/j, in diameter with alternate promi- 

 nent and weak rows of punctuations, and the tip distinctly set off 

 from the rest of the cell; var. laticlavius (Hubner), 130/x in length 

 and 20/x in diameter with weakly but uniformly developed rows 

 of punctuations, and var. marchia Lemm., 79-100/^ in length and 

 6-12/x in diameter with equally developed rows of punctuations 

 which are almost in contact with one another. 



