The most striking conclusion that comes out of the study of this evidence of frequent deficiency among delinquent girls and women is the close association between sex offenses and deficiency. One hundred and four out of 118 consecutive admissions at the Illinois training school were known to be sexually immoral. At Bedford 94 out of 100 consecutive cases had records of immorality, while three-fourths of the same group tested questionable in intellect by our standards (_11_). This evidence, taken with the report of the Massachusetts' Commission and the tests of sex offenders who were not at the time legally delinquents, reported by McCord, and the Virginia Commission, leaves little doubt that there is an excess of deficiency among this type of offender. Many of these deficient girls probably at first drift into the life of prostitution. They are passive rather than active agents. This distinction in the nature of the offense accounts for some of the difference between the sexes in this form of delinquency. Furthermore our public attitude in matters of social hygiene has made the isolation of the female sex more common. Part of this may be due to the greater difficulty of proof in the case of men and boys, but in part it undoubtedly means that men have not been held to as high a moral standard as women in this regard. The greater frequency of deficient sex offenders among girls, does not mean that girls are more likely than boys to be active sex offenders. They are, however, more likely to be isolated for such offenses, and also more likely to be passive offenders. The greater amount of deficiency found among female delinquents than among corresponding groups of males is thus easily accounted for by frequent association between deficiency and sex delinquency on the part of girls and women. The combination of legal sex delinquency and deficiency is due both to a native sex difference and a difference in social attitude toward the two sexes as to this form of offense. Whichever may be the main cause of the facts found, it is clear that deficiency is, today, most serious among female offenders. It is so serious that some of our reformatories for women might even prove to be practically institutions for deficient delinquents. It is in this type of institution without doubt, that the immediate problem of the deficient delinquent is most pressing. Permanent guardianship, if not isolation, for at least a third of the inmates of an institution like Bedford which shows this amount of clear tested deficiency, under our very conservative standard, would seem to be a wise move in social hygiene. It should be undertaken at once with vigor. A more fundamental change in our social attack of this problem means state guardianship before adolescence for all girls testing presumably deficient under our standard, when their deficiency is not due to removable handicaps. (c) MEN AND BOY DELINQUENTS IN STATE INSTITUTIONS.