A s 



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A study during 1907 and 1908 of various plots of wheat cut 

 at three day intervals leads to the following general conclusions: 



1) The whole plant and with it the nitrogen, ash, and pho- 

 sphoric acid it contains increases in weight until about a week 

 before it would be regarded as ready to cut. Some increase of 

 dry weight takes place during the last week. 



2) In the formation of the grain three stages may be distin- 

 guished a) a period during which the pericarp is the most prominent 

 feature ; b) the main period during which the endosperm is filled ; 

 c) the ripening period characterised by the desiccation of the grain. 



3) For the filling of the endosperm each plant possesses as 

 were a special mould, and continually moves into the grain 



uniform material cast in that mould, possessing always the same 

 ratio of nitrogenous to non-nitrogenous materials and ash. The 

 character of the mould possessed by each plant is determined by 

 variety, soil, season etc. 



4) The main feature of the ripening process is desiccation 

 rather than the setting in of such chemical changes as the con- 

 version of sugars into starch, non-protein into protein, though the 

 latter change also takes place. 



5) The maximum dry weight of grain is attained a day or 

 two before the grain would be regarded as ripe by the farmer. 

 Allowing for the fact that the tillered shoots are a little behind 

 the central shoots, no loss of weight in the crop will be incurred 

 by cutting before the corn appears quite ripe, while a number of 

 accidental mechanical losses due to birds, shedding, weather, may 

 thus be avoided. Other experiments have shown that, though 

 there may be no gain, there will be no loss in the quality of the 

 wheat due to such early cutting. 



H. S. REED. The effect of certain chemical agents upon the 

 transpiration and growth of wheat seedlings. ^/. Gaz., 



49, 1910, 2, 81-109). E. S. ., June 1910. 



The small amounts ot the chemical agents used (lime, sodium 

 phosphate, potassium salts, sodium nitrate, inorganic acids, etc.) had 

 a definite influence upon the correlative transpiration. The effects 

 produced in all cases seemed to be due to the specific action of 

 the ions constituting any given agent. Potassium always showed 

 its inhibiting action on transpiration, regardless of whether it was 

 in combination with chlorine, nitric acid, or sulphuric acid. The 

 stimulating effect of calcium was shown in a similar way. 





