The fundamental importance of accurate standards for hemoglobin content, number of red blood cells and volume of packed cells in the venous blood of normal persons is definitely recognized. Application of these normal values to the study of the various forms of anemia has given the standards clinical as well as academic importance. Possible variations in the normal range of values can be investigated only by comparison of the results of analyses of samples of blood from persons living in a number of widely separated localities which differ in climate and altitude. This comparative study may ultimately make possible the adoption of universal standards or may necessitate the establishment of separate standards for different regions.
Extensive studies of the venous blood of adults have been made in the United States by Haden,1 in Kansas City, Mo., Cleveland and Detroit; Osgood and Haskins,2 in Portland, Ore.; Wintrobe and Miller,