INTRODUCTION. f 



will do much for the progress of agricultural sciences. It is true 

 that in some small countries the variations in the environment are 

 not sufficiently great to enable studies of a similar character to be 

 carried ni. yet there are many single States in our own country 

 whose areas and consequent variations of environment are sufficient 

 to permit studies of great value to be carried on within their borders. 

 As an illustration of this, Texas, for instance, affords such variations 

 in environment that studies of this kind might be undertaken within 

 its borders. Fortunately, by reason of the relations which exist 

 between the central government and the various States in this country 

 it is an easy matter to secure the collaboration of a sufficient number 

 of Static to widely extend these studies of environment. Un- 

 doubtedly similar collaborative studies could be profitably made 

 by countries. For instance, on the continent of North America it 

 might be very easy to interest both the Dominion of Canada and 

 Mexico in studies of the effect of environment on the composition of 

 plants which would grow in nil three countries. Thus the line of 

 study which has been indicated by these investigations may be 

 pursued in the future with much more useful results by others. 



It is evident that the character of a food plant, as far as its physical 

 and organoleptic properties are concerned, is largely the result of 

 chemical composition. Hence it follows that if we can place in the 

 hands of the farmer the means of influencing this chemical com- 

 position much may be accomplished toward the improvement of 

 plants and their adaptability to the particular purpose for which 

 they are intended. Combined as this study naturally is with that 

 of M-lection for improvement, it affords an almost perfect means of 

 variation at the will of the experimenter who may have at his dis- 

 posal the variations in environment which are dominant in producing 

 chemical change. While perhaps it is idle to look forward to a time 

 when the environment itself may be subject to variation through 

 human means, it is not difficult, in a limited way, to produce changes 

 in environment at the present time by growing plants under glass. 

 Thus a way may be opened for studying effects of environment 

 within a very small area of the United States. While such a study 

 would be full of the greatest scientific interest, it could not possibly 

 have the same practical value as a study made under natural 

 conditions. 



The original plan under which these studies were mapped out 

 included also studies of the effect of environment on the protein 

 content of cereals and the sugar content of melons. Much pre- 

 liminary work has been done along these lines, but not enough to 

 warrant publication at the present time. The data secured show, 

 however, that these are promising fields of research. 



