AQUATIC hWn 135 



Chart I represents the data taken on the following days m 

 1916. June 22, 23, 29. July 7, 13, 21, 24, 26, 28. August 2, 4, 8, 16, 

 22. On each trip a smiilar chart was used and at the end of the 

 summer the average temperature, turbidity and carbon dioxide 

 content was calculated. Chart I shows the average at each 

 station. Thus fourteen charts similar to I and II were made, 

 denoting fourteen trips to each station and from the data taken at 

 each station the following conclusions were drawn. 



Stations I and II. Very shallow; temperature variable; 

 bottom covered with decomposed plant life. The Entomostraca 

 which feed on plants, desmids, diatoms, etc., were quite abundant. 

 The greater the rainfall the more abundant the Entomostraca at 

 all of the stations. 3 c. c. of carbon dioxide per 1000. No e;aect on 

 forms found at such a low per cent. 



Station III. Comparatively deep. Carbon dioxide content 

 high, 20 c. c. per 1000. Bacterial growth abundant. Numerous 

 Entomostraca in nauplius stage. Adults found more numerous at 

 Station IV where vegetation was more plentiful. The number and 

 genera fluctuated from day to day due to the current from the 

 sewer channel. 



Station V. This station was one of the deepest in the Cove 

 and although fewer forms were found here their number and kind 

 were more constant. It was found by taking three horizontal 

 towings that the Entomostraca tend to be uniformly distributed 

 in a horizontal plane having the maximum number about 2 feet 

 below the surface and the minimum at the bottom. The nauplius 

 stage appeared first in the upper waters of the Cove quite near the 

 surface. Increase in population results in extension downward, 

 and the mass becomes most uniformly distributed at its maximum 

 developement. With decline of production there is a relative 

 increase in numbers in the lower waters. Common sunfish {Eupo- 

 motis gibhosus) were feeding on the surface forms. 



Station VI. Located near shore having similar surroundings 

 and environment that existed at Stations I and II. The forms 

 frequently found here were Daphnia, vSimocephalus, Chydorus. 

 Sunfish had built their nests at this point and fed upon these forms. 

 It is estimated that one Daphnia pulex (female) may have a progeny 

 of 13,000,000,000 in sixty days. It is little wonder then that the 

 Entomostraca form one of the chief foods for fishes. It was also 

 noted that when large numbers of Daphnia occurred and a cloud 



