236 Nitrificiitw)! in Effi/pfiaii Soils 



Tlie "slieraqi" soils of the summer fallow are biologically dormant. 

 Tlu\\- are characterised by very low moisture content and by fairly 

 high temperatures, particularly in the basins of Upper Egypt. There 

 is a probability that these conditions act as a partial sterilisation of 

 the soil. 



Pot experiments are described concerning the effect of the growth 

 of maize and of wheat on the accumulation of nitrate in the soil. 



Bahtim Experimental Station, 

 iMar'ch, 1910. 



{Received Ma// Mill, I'Jl'J.) 



