[85] As a result of psychiatric study of the inmates of Sing Sing in 1916, it was said that two-thirds of them showed some mental defect. Examination of 100 convicts selected at random in the Massachusetts State Prison showed that 29% were feeble-minded and 11% borderline cases. The highest percentage of mental defectives was found among criminals serving sentence for murder in the second degree, manslaughter, burglary and robbery. (Rossy, C. S., in _State Board of Insanity Bull._, Boston, Nov., 1915). Paul M. Bowers told the 1916 meeting of the American Prison Association of his study of 100 recidivists, each of whom had been convicted not fewer than four times. Of these 12 were insane, 23 feeble-minded and 10 epileptic, and in each case Dr. Bowers said the mental defect bore a direct causal relation to the crime committed. Such studies argue for the need of a little elementary biology in the administration of justice. [86] For a sane and cautious discussion of the subject see Wallin, J. E. W., "A Program for the State Care of the Feeble-Minded and Epileptic," _School and Society_, IV, pp. 724-731, New York, Nov. 11, 1916. [87] Johnstone, E. R., "Waste Land Plus Waste Humanity," _Training School Bulletin_, XI, pp. 60-63, Vineland, N. J., June, 1914. [88] "Report of the Committee on the Sterilization of Criminals," _Journal of the Institute of Criminal Law and Criminology_, September, 1916. Of the operations mentioned, 634 are said to have been performed on insane persons and one on a criminal. [89] Guyer, M. F., Wisconsin Eugenics Legislation. Trans. Amer. Asso. Study and Prevention of Infant Mortality, 1917, pp. 92-97. [90] Eugenics Record Office, Bulletin No. 10 A, _The Scope of the Committee's Work_, Cold Spring Harbor, L. I., Feb., 1914; No. 10 B, _The Legal, Legislative and Administrative Aspects of Sterilization_, same date. [91] Eugenics Record Office Bulletin No. 9: _State Laws Limiting Marriage Selection Examined in the Light of Eugenics_. Cold Spring Harbor, L. I., June, 1913. [92] Penrose, Clement A., _Sanitary Conditions in the Bahama Islands_, Geographical Society of Baltimore, 1905. [93] See von. Gruber and Ruedin, _Fortpflanzung, Vererbung, Rassenhygiene_, p. 169, Muenchen, 1911. [94] Davenport, Charles B., _Heredity in Relation to Eugenics_, pp. 184 ff., New York, 1911. [95] Harris, J. Arthur, "Assortative Mating in Man," _Popular Science Monthly_, LXXX, pp. 476-493, May, 1912. The most important studies on the subject are cited by Dr. Harris. [96] An interesting and critical treatment of sexual selection is given by Vernon L. Kellogg in _Darwinism To-day_, pp. 106-128 (New York, 1908). Darwin's own discussion (_The Descent of Man_) is still very well worth reading, if the reader is on his guard. The best general treatment of the theory of sexual selection, especially as it applies to man, is in chapter XI of Karl Pearson's _Grammar of Science_ (2d ed., London, 1900).