Vol. VII. Part 2 September, 1915 



THE 



JOURNAL 



OF 



AGRICULTURAL SCIENCE 



EDITED BY 



Professor R. H. BIFFEN, M.A., F.R.S., Cambridge 

 A. D. HALL, M.A., F.R.S., Development Commission, London 

 E. J. RUSSELL, D.Sc, Rothamsted Experimental Station 

 Professor T. B. WOOD, M.A., Cambridge 



IN CONSULTATION WITH 



Dr H. p. ARMSBY, State College, Pennsylvania, U.S.A. 



B. C. ASTON, Department of Agriculture, Wellington, New Zealand 



Dr C. a. barber, Agricultural College, Coimbatore, India 



Professor B. T.-P. BARKER, M.A., National Fruit and Cider Institute, Long Ashton, Bristol 



W. BATESON, M.A., F.R.S., John Innes Horticultural Institute, Merton, Surrey 



J. R. CAMPBELL, B.Sc, Department of Agriculture, Dublin 



I. B. POLE EVANS, Department of Agriculture, Pretoria, South Africa 



F. B. GUTHRIE, Department of Agriculture, Sydney, N.S.W. 



Professor J. HENDRICK, B.Sc, Marischal College, Aberdeen 



J. W. LEATHER, V.D., F.I.C., Agricultural Research Institute, Pusa, Bengal 



T. H. MIDDLETON, C.B., M.A., Board of Agriculture, London 



F. T. SHUTT, M.A., F.I.C., Experimental Farms, Ottawa, Canada 



Professor W. SOMERVILLE, M.A., D.Sc, School of Rural Economy, Oxford 



Dr a. C. TRUE, Department of Agriculture, Washington, DC, U.S.A. 



Dr FRANCIS WATTS, C.M.G., Barbados 



Dr H. J. WHEELER, American Agricultural Chemical Co., Boston, Mass 



Cambridge University Press 



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 [Issued September 7, 1915.] 



