Lake Maxinkuckee, Physical and Biological Survey 49 



leaf coatings often drop off as casts and are to be found lying 

 heaped up about the bases of the plants. The so-called ditch-moss, 

 Philotria, is an energetic lime gatherer; indeed, all the other sub- 

 mersed plants in the lake possess this same property and contribute 

 in the aggregate in no inconsiderable degree to the amount of marl 

 in the bottom of the lake. 



In addition to the mollusks and plants there are still other 

 organisms which play a part in the formation of marl; among 

 these are the various species of crustaceans, particularly the craw- 

 fishes, whose shells contain calcic compounds. 



The rate of deposition of lime in the lake is quite difficult to 

 estim.ate. It was probably more rapid during the early life of 

 the lake when the amount of calcium carbonate in the water was 

 greater than it now is. Even at best the rate must be very slow, 

 indeed. An annual deposit of one-hundredth of an inch has been 

 estimated. A deposit of 10 feet would therefore require 12,000 

 years as the age of the lake. But this is scarcely more than a 

 mere guess, and signifies very little. 



The Lake Level 



Stage of water: — The mean elevation of the surface of the 

 water of Lake Maxinkuckee above sea level at Biloxi, Mississippi, 

 is 734.5 feet. Records kept by the Office of Engineer, Maintenance 

 of Way, of the Terre Haute and Logansport Railway Company, 

 from October 18, 1895, to May 7, 1900, totaling about 50 observa- 

 tions, show that the lowest water in that period occurred on Octo- 

 ber 18, 1895, when it stood at 733.30 feet. The highest, 735.21 

 feet, was recorded March 13, 1899. The extreme variation was 

 therefore 1.91 feet or 22.92 inches. 



Our party began making observations on the stage of the water 

 in the lake on August 14, 1900. On that date a three-foot rule, 

 graduated to inches, was properly installed at the side of the 

 wagon bridge which crosses the Outlet just as it leaves the lake. 

 The position of this gauge was correlated with that of the up- 

 stream girder of the railroad bridge, which crosses the Outlet 27 

 feet below the wagon bridge. Readings were taken from time to 

 time from that date up to October 22, 1913. The lowest water was 

 recorded November 3, 1908, and the highest July 8, 1902. 



Starting with the extreme low water of November 3, 1908, as 

 "zero" and reducing all observations to that basis, we have the 

 following table: 



