L. J. Wild 177 



under-drainage and high rainfall, which prevents aeration and oxidation 

 of organic matter, so that "sour" humus accumulates in the soil. 



In conclusion the author desires to acknowledge the assistance of 

 his predecessor, Mr George Gray, F.C.S., who has kindly allowed him 

 the use of many hitherto unpubhshed analyses; and of his students, 

 Mr N. M. Paulsen, M.A. for assistance with the chemical analysis, and 

 Messrs 0. C. Stephens and N. P. Neal for assistance with the mechanical 

 analysis of a great many soils. 



{Received August 1st, 1916.) 



