144 CARNEGIE INSTITUTION OF WASHINGTON. 



STATISTICAL THEORY OF PLOT TESTS. 



Studies of field heterogeneity in relation to the problem of the accur- 

 acy of plot tests of new varieties have been under way at this Station 

 for the past several years. Some time ago the Office of Western Irri- 

 gation Agriculture of the United States Department of Agriculture 

 asked our cooperation on this problem and work has since been con- 

 ducted largely on the data and with the support of the Department of 

 Agriculture. A first paper, in which substratum heterogeneity was 

 shown to be a universal factor of significance in plot tests, has been pub- 

 lished by Dr. Harris (Jour. Agr. Res., vol. xix, 279-314, July 1, 1919), 

 and another, in which the permanence of the differences in the small 

 plots of an apparently uniform field and the influence of preceding 

 upon subsequent crops are discussed, is now ready for publication. 



COOPERATIVE WORK ON HUMAN NUTRITION. 



Studies of variation and correlation in the basal metabolism of the 

 individual subject have been under way by Dr. Harris, in cooperation 

 with the Director of the Nutrition Laboratory of the Institution. 

 The results are practically ready for publication. 



