The nuclei in the skin, and in the neutrophils, have been studied in men and women, in relation to a diagnosis of the sex chromosomes in non-dividing nuclei. It has been shown in the skin, that the appearance of chromocenters, which are presumably formed by the X and Y, can vary according to metabolic conditions, but that a determination of the percent of nuclei with different numbers of chromocenters and nucleoli in the young and old spinous cells, gives a characteristic distribution of nuclear types in each of the two sexes. Since such a determination includes cells with individual X and Y chromocenters, it should be possible to detect by this method not only cases that are XX or XY, but also cases with abnormal sex chromosome constitutions.