374 



BOTANICAL GAZETTE [November 



is required. More than three times as much oxygen was required 

 by the bog water as by lake water. 



The large amount of solid organic matter in bog water is 

 evidently the result to a large extent of the breaking down of 

 plant tissues in the absence of an adequate supply of oxygen. 

 The interstices of the decaying mass of material are full of water 

 at all times at a depth of 2 ft. or more, and even in the first 2 ft. 

 except occasionally for a brief time in midsummer. Since organ- 

 isms are abundant in bogs, it seems evident that the nature of 

 the products must be conditioned by at least 3 factors: (i) the 

 original composition of the decaying materials, (2) the organisms 

 present, (3) the environmental conditions under which they act. 

 Dachnowski (5, 6) has emphasized the reducing power of bog 

 soils, and has found that aeration lowers the toxicity of the water 

 to agricultural plants. Klein (9) had made suggestions along 

 this line as early as 1880. 



A very large amount of the nitrogen present in bog water is 

 in the organic form. The total organic nitrogen content of the 

 bog water here reported is over three times as much as that of the 

 lake water reported. In the bog water the total organic nitrogen 

 is 50 times the combined nitrite and nitrate content, while in the 

 lake water it is only 14 times. 



The work of Jodidi (8) and of Robinson (16) show large 

 amounts of nitrogenous matter in bog soils, and indicate that it 

 is either already in the form of amino acids and acid amides, or is 

 capable of being converted readily into these compounds. 



The amount of nitrogen as nitrates is slightly larger in the 

 lake water than in the bog water. Even if this difference were 

 large it could not be accepted as necessarily indicating a difference 

 between the nutritive value of the two waters for plants, since it 

 is well known that some organic compounds are beneficial to plant 

 growth (2, 4, 17, 19). A number of these beneficial organic com- 

 pounds are nitrogenous. Bottomley's (2) work indicates the 

 abundance of such a compound in sphagnum peat that has been 

 acted upon by aerobic soil organisms. 



The amount of nitrogen as free and albuminoid ammonia 

 varies considerably in the different analyses, and the existence of 



