A STUDY OF RELATIONS BETWEEN PLANT GROWTH. 



339 



A region of this nature was that along the shore of the island made by the 

 canal. This region was close to the town and received a considerable amount 

 of sewage, but supported only a moderate plant growth. The region gave 

 upon analysis a content quite close to that of the open lake, as can be seen 

 by comparison of stations C and U in Figs. 1, 5. Station U had a sparse growth 

 of various Potamogetons. Its location is shown on the map. 



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Pig. .5 — Map af Stations in Soutli Bay. 



Five stations in South Bay were intermediate between this condition and 

 the next, and it was found that the contents of the five stations were nearly 

 identical at any given date, although the stations were very diverse as to 

 plant growth. 



The map (Fig. 5) shows the relations of the stations which are also de- 

 scribed in the list giving the characteristics of the stations. The general 

 region is indicated on the map of the lake (Fig. 1) by the letter S. 



There was a distinct and fairly constant relation between the stations 

 as shown by the analyses but no opportunity was afforded for an accumulation 

 of any form of nitrogen due to the fact that the ciirrents kept the region mixed. 

 See figure 14 for graphs for these stations. 



