PREFACE Ix 



too closely in the investigations which were made before 

 the end of last century, with the result that many field 

 experiments have expressed the net result of many 

 conflicting factors, and have given but little indication as 

 to the components. 



On my appointment to the staff of the Khedivial 

 Agricultural Society at the end of 1904, as Cryptogamic 

 Botanist, and hence specialising on heredity and physiology 

 in cotton — on account of the innate perversity of things 

 Egyptian — I decided to abandon the accepted method of 

 crop-inspection on a large scale, and to substitute detailed 

 examination of a few plants. The literature then extant 

 gave scarcely any assistance to such heterodox procedure, 

 and the story of the researches which followed from this 

 decision has been written on a tolerably clean sheet. 



The work began as Genetics, but necessarily extended 

 into Physiology. This mental transition was accelerated 

 by the pronounced deterioration of the Egyptian crop, 

 both in yield and quality, which began to be obvious in 

 1905, and culminated in the catastrophic failure of the 

 1909 crop. The physiological researches necessitated by 

 demands for information as to the possible effects of 

 unsuitable soil-water conditions have given results of 

 more immediate interest, and of greater novelty, than 

 the weary routine accumulation of critical data for 

 Mendelian analysis, though the latter are probably of 

 higher intrinsic value. 



For years it had been intended to establish a suitable 

 field laboratory in which the work could be conducted 

 efficiently, but, owing to various causes, this establishment 

 was delayed, and it has taken from December 13th, 1907, 

 when the resolution was passed, till March, 1912, to 



