1. Intellectual deficiency as a social problem is undoubtedly at present most serious among women and girls who are sex offenders. It is this fact which accounts for the excessive amount of deficiency found in the industrial schools for girls, and the reformatories for women. It is not necessary to repeat the discussion of the reasons for this which were considered at the close of the studies of women delinquents. The most closely corresponding class of male delinquents is probably the “vags,” as Aschaffenburg suggests (_68_, p. 162). The vagrants form a much smaller portion of the inmates of the institutions for male delinquents than do the prostitutes in the institutions for women and girls. The little evidence we have indicates, moreover, that as a class the ne'er-do-wells average higher in ability than the prostitutes. They are, probably, a more mixed group. As reported by Terman (_57_), Mr. Kollin found among 150 “hoboes” at least 20 per cent. belonged to the “moron grade of mental deficiency.” * * * “The above findings have been fully paralleled by Mr. Glen Johnson and Professor Eleanor Rowland, of Reed College, who tested 108 unemployed charity cases in Portland, Oregon” (_57_, p. 18). Since these investigators used the Stanford Scale, the borderline was probably set at the position where it would exclude about 1% of the ordinary population, a little more conservative than our doubtful group. We should know more about deficiency among the typical “Weary Willies,” since it is likely that courts are accustomed to assume that vagrancy is a habit which can be corrected by a term in the workhouse. There is little doubt that mental deficients fill up the recruiting stations for the prostitutes and “vags.” It is with these classes that the most intensive social work should be done in the campaign for early isolation of the unfit.