56. Goddard, H. H. _The Kallikak Family._ The Macmillan Company. (1914.) 121 pages. An epoch-making study of the hereditary transmission of mental deficiency in a degenerate family. 57. Holmes, Arthur. _The Conservation of the Child._ J. B. Lippincott Company. (1912.) 345 pages. Methods of examination and treatment of defective children. 58. Holmes, Arthur. _The Backward Child._ Bobbs-Merrill Company. (1915.) A popular treatment of the handling of backward children. 59. Huey, E. B. _Backward and Feeble-Minded Children._ Warwick & York. (1912.) 221 pages. Devoted mainly to clinical accounts of borderline cases. 60. Lapage, C. P. _Feeble-Mindedness in Children of School Age._ The University Press, Manchester, England. (1911.) 359 pages. 61. Sherlock, E. B. _The Feeble-Minded; A Guide to Study and Practice._ The Macmillan Company. (1911.) 327 pages. 62. Tredgold, A. F. _Mental Deficiency (Amentia)._ Baillière, Tindall, and Cox. London, England. (2d ed. 1914.) 491 pages. The best medical treatment of the subject. STUDIES OF THE PROGRESS OF CHILDREN THROUGH THE GRADES 63. Ayres, Leonard P. _Laggards in our Schools._ The Russell Sage Foundation. (1909.) 236 pages. Interesting and instructive discussion of school retardation and its causes. 64. Blan, Louis B. _A Special Study of the Incidence of Retardation._ Teachers College, Columbia University, Contributions to Education, no. 40. (1911.) 111 pages. Review of the literature and a statistical study of the progress of 4579 children. 65. Keyes, C. H. _Progress Through the Grades of City Schools._ Teachers College, Columbia University, Contributions to Education, no. 42. (1911.) 79 pages. Important study of the progress of several thousand children. 66. Strayer, George D. _Age and Grade Census of Schools and Colleges._ Bulletin no. 451, U.S. Bureau of Education. (1911.) 144 pages. Statistics of the age-grade status of the children in 318 cities. 67. See also the _Reports_ of leading school surveys, such as those of New York, Salt Lake City, Butte, Springfield (Mass.), Denver, Cleveland, etc. REFERENCES ON THE SPECIAL CLASS FOR EXCEPTIONAL CHILDREN 68. Huey, E. B. "The Education of Defectives and the Training of Teachers for Special Classes"; in _Journal of Educational Psychology_ (1913), pp. 545-50. 69. Goddard, H. H. _School Training of Defective Children._ World Book Company. (1914.) 97 pages. Based on his survey of the treatment of backward children in the schools of New York City. 70. Holmes, W. H. _School Organization and the Individual Child._ The Davis Press, Worcester, Massachusetts. (1912.) 211 pages. A comprehensive account of the efforts which have been made to adjust the school to the capacities of individual children.