November 5, 1920] 



SCIENCE 



447 



protein content of wheat correspond with the 

 length of the period of the different deferred 

 applications of nitrate made after planting, 

 this would indicate a significant relation 

 between the state of development of the plant 

 and when nitrate can be most effectively 

 utilized by the plant in the production of 

 high protein wheat. This emphasizes that 

 the physiological status of the plant, as indi- 

 cated in its different growth phases, is a 

 factor of great importance in the utilization 

 of plant food available to it. 



Not only was the protein content of the 

 wheat increased by all of the deferred appli- 

 cations of nitrogen, but the yield of produce, 

 excepting that obtained by the latest applica- 

 tion, was much larger from the plants that 

 received nitrogen for the period of 33 to Y2 

 days after planting than those that received 

 nitrogen during the early growing period. 

 The best quality wheat as determined by com- 

 mercial grading was secured from the plants 

 that received nitrogen 72 and 110 days after 

 planting. This means that the high protein 

 wheat berry was likewise plump and well 

 filled. 



A much fuller account of the investigation 

 with ample analytical data and a critical re- 

 view of other investigations relating to the 

 subject will shortly appear. It is felt that 

 the results obtained in this investigation do 

 show that the low protein content of Pacific 

 states wheats is not due primarily to the 

 climate as such, but so far as the investiga- 

 tion with this one soil is concerned, is due to 

 insufficiency of available nitrogen at certain 

 growth periods of the plants. That climate 

 is not without effect upon the availability of 

 the plant food in the soil is obvious, but the 

 emphasis to be laid on the climatic complex 

 is that it affects the nutrition of the plant. 

 This can be both in the kind and quantity 

 of each of the different nutrients that may be 

 available to it. That this availability is an 

 important factor in affecting the composition 

 of plant products is shown by the results of 

 this investigation. 



W. F. Gericke 



Universitt or California 



THE VITAMINE REQUIREMENTS OF THE RAT 

 ON DIETS RICH IN PROTEIN, CARBOHY- 

 DRATE, AND FAT RESPECTIVELY' 



In 1913, one of us (C.F.) showed that the 

 onset of the symptoms of beriberi in pigeons 

 could be hastened by increasing the amount 

 of polished rice fed. This led to the conclu- 

 sion that the anti-beriberi vitamine — vitamine 

 B — plays an important role in carbohydrate 

 metabolism. This observation was confirmed 

 shortly afterwards by Braddon and Cooper 

 and others, although Eijkman and Vedder 

 have denied the validity of this finding. 



In a second series of experiments, in which 

 the diets varied as shown in Table I., it will 

 be noticed that beriberi developed in the fol- 

 lowing order: starch, sugar, casein, and fat. 



In order to check up the results obtained 

 with pigeons in another class of animals, and 

 also with the idea of attempting to throw 

 some light on the prevailing view as to the 

 importance of proteins of high biological 

 value on the etiology of pellagra and war 

 edema, analogous experiments have been 

 carried out on rats. The composition of the 

 diets and the results obtained are shown in 

 Tables II. and III. 



1 From the Research Laboratory of H. A. Metz. 



2 The meat, sugar, starch, and lard were tested 

 and found to be free from Vitamine B. 



