In Reply.—
We thank Tomases and Bessman for their comments. Tomases points out correctly that our subjects were not fully representative of the population as a whole, but consisted of healthy employees of the federal government (most of whom were active-duty soldiers). We purposely chose this group of subjects so that our data would reflect the "normal range" of values within the general population, without including any subjects whose abnormal hemogram values were related to serious illness. Bessman's comments are appreciated and may provide a plausible explanation for the mean corpuscular volume data that we observed. We were cautious in describing and interpreting these data because of relatively small numbers of subjects with values in the lower ranges.It also should be noted that the article's1 abstract contained an inadvertent transposition of numbers in the hemoglobin data. The mean hemoglobin concentrations for white and black men were 153 and