In 1929, the area was extended to cover all of the lake east 

 of Western Lake Erie, and sanples were taken in Jvine, July, August, and 

 September (Burkholder, unpublished manuscript). Diatoms were most 

 abundant in June and September. In June the hif:;hest count was made on 

 the south shore near Fairport (about U6 thousand units per liter). Most 

 of the stations had much lower counts, and the average (not given) would 

 be much less than the average for Western Lake Erie in the same month. 

 In July the diatoms almost disappeared in the central basin, but east of 

 Long Point several stations had counts of 10 thousand or more. In 

 August the diatoms were rare everywhere, but in September the abundance 

 increased markedly in the central basin. The highest count was recorded 

 for a station near Cleveland (about 230 thousand). The average for the 

 three stations nearest Western Lake Erie was about 55 thousand, which 

 was above the average for the whole area, and well below the average for 

 Western Lake Erie in September (Figure 13). Asterionella, Fragilaria, 

 Melosira, and Tabellaria were the dominant genera. 



It should be mentioned here that Burkholder 's results disagree 

 with those obtained by Gottschall (1930) with regard to the abundance of 

 diatoms near the port of Erie. Gottschall took collections from the 

 intake pipe of the Erie water supply. The outer end of the intake pipe 

 is not far from one of Burkholder 's stations, and one would expect 

 counts from the two sources to be somewhat alike. For August and 

 September, 1929, Gottschall reported counts ranging from about 20 

 thousand to about 600 thousand units per liter, while the counts from 

 Burkholder 's station nearby did not exceed 2 thousand. It would be of 

 considerable interest and importance to know which set of results most 

 nearly approximates the true condition in the lake. 



The green algae were rare everywhere in June, but increased 

 somewhat at certain stations in July and August. Few stations showed 

 counts above one thousand per liter. This group was most abundant in 

 September, when several stations yielded counts of about 5 thousand. 

 At no place, even at the three stations farthest west, did the abun- 

 dance approach the average of the Island Section for September (Figure 15) 

 The common genera were Coelastrura, Dictyosphaerium, Pediastrum, and 

 Sphaerocystis, 



In June the blue-gicen algae were concentrated at the surface 

 in the central basin, and were almost absent from the section east of 



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