100 The Ohio Journal of Science [Vol. XVI, No. 3, 



Summary and Conclusions — Transpiration loss, so far as 

 measured by the evaporating power of the air, is definitely 

 correlated with physical exposure and zonal distribution of 

 plants in the marsh studied. 



Topography, substratum, direction of prevailing wind, and 

 thickness of vegetative cover all find logical expression in the 

 evaporation percentages obtained. 



Evaporation must be assigned an important role coordinate 

 with such fundamental factors as water depth and organic 

 content of substratum in interpreting the plant distribution in 

 the marsh under examination. 



The writer feels under considerable obligation to Dr. 

 Raymond J. Pool, of the University of Nebraska, Dr. E. N. 

 Transeau of Ohio State University, and to the staff of the Ohio 

 State Lake Laboratory for courtesies and suggestions during 

 the course of the work and the writing of the paper presented 

 above. 



Bibliography. 



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4. Weaver. Evaporation and Plant Successions in Southeastern Idaho. PI. 



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