In studying the lives of these individuals for the factors which have determined their mode of life, there are several physical characteristics which should be mentioned. First, the perfectly normal condition of adolescence is always to be taken into consideration. In many cases of individuals with less than normal stability and insufficiently protected environment, it has been the adolescent tendencies which have been the dominant factor in determining their life. Again, the factor of too early development has often been seen. Puberty appears before the inhibitions which come with adolescence have had time to be correspondingly developed. This is a very noticeable factor in the study of such cases found in the juvenile court, and has been recognized in our own cases and verified by the histories obtained from the parents of the individual. Besides these factors, there is the type in which the physical characteristics predominate from birth. While it may be possible for these individuals to have their energy directed along constructive lines, it is often impossible to reach them and recognize their struggles until habits of an unfortunate nature have been irrevocably formed in their lives. _Summary._ In reviewing the 240 cases, which we appreciate represent the types which come to reformatories and are not necessarily characteristic of all types of prostitution in society, we find the following facts: 52 per cent. defective; 16 per cent. dull; 28 of the remaining 67 cases with normal mentality showed other mental and nervous defects. Only 15 per cent. of the whole number appeared to be normal mentally and physically. Probably 40 per cent. could be considered segregable types and should be placed permanently, or at least during the child-bearing age, in custodial institutions. If these cases who are apparently unable to care for themselves could be removed from the community, we believe the supply for prostitution would be materially lessened and that such a movement would be a help in attacking the problem. As has already been said, practically 100 per cent. of the cases studied show the presence of at least one of the two venereal diseases, while over 55 show the presence of both. Of the cases studied for evidence of syphilis, over 65 per cent. had had the disease; of those studied for gonorrhoea over 96 per cent. gave evidence of having had it. Should we not recognize the far-reaching results of such diseases in a community and use every means possible to help eliminate them?