DEPARTMENT OF GENETICS. 113 



the intermediacy of special organs that influence metabolism, notably the 

 endocrine glands. In some cases, at least, three independent factors are 

 involved in very fleshy build, but the number is not the same in all biotypes; 

 in some there is only one, in others 4 or more. 



Further collections of family data on body-build are being made by Miss 

 Louise A. Nelson under the Lawrence Memorial Research fund of the Play- 

 ground Athletic League, of which Mr. Robert Garrett is president and 

 Dr. William Burdick is director. 



Heredity of Radio-Ulnar Synostosis. 

 In cooperation with Dr. Henry Ling Taylor, the New York paediatrician, 

 a study was made on the heredity of a relatively rare condition by which 

 radius and ulna are congenitally fused at their proximal end. With the 

 assistance of Miss Louise A. Nelson, who did the field work, 15 families were 

 studied; 23 new cases are listed and described; they fall into two types. 

 A review of the mammals shows that proximal radio-ulnar synostosis is not 

 rare. In man the condition is often associated with other bony defects. 

 In most families the inheritance is that of a 2-gene trait, in others of a 3-gene 

 trait. In one family the single gene appears to be in the Y-chromosome. 

 Always synostosis is dominant. Males are twice as apt to be affected as 

 females, taking all families together. Consanguineous matings are frequent 

 in synostotic families. A review of the literature as compiled by Miss Mabel 

 L. Earle accompanies the paper. 



Correlation Between Physical and Mental Development in Man. 

 At intervals, further measurements of idiot boys have been made by the 

 Director at Letchworth Village, with the kind cooperation of Dr. Charles S. 

 Little, superintendent. One paper by Dr. Bertha E. Martin and myself, 

 embodying the earlier studies, is in press, and further analyses of the data 

 were made by Dr. Martin in the summer of 1923. Miss Louise A. Nelson 

 made field studies in central New York State upon the families of these boys. 



Variation, Correlation, and Racial Differentiation in the New-Born Infant. 



The statistical investigation of the data for new-born infants, abstracted 

 from the records of the Sloane Hospital for Women, New York City, has 

 been continued by Dr. Harris. 



GENETIC CONSTITUTION OF THE AMERICAN POPULATION. 



EuGENicAL Sterilization. 

 In December 1922 the volume on "Eugenical Sterilization in the United 

 States," prepared by Dr. H. H. Laughlin, was published by the Municipal 

 Court of Chicago. Chapter headings are as follows: 



Chapter I. Chronological Ust of laws, amendments, executive vetoes, repeals, official 

 legal opinions, board orders, and court decisions relating to eugenical sterilization 

 previous to January 1, 1922. 



Chapter II. Analysis, by States, of sterihzation laws enacted prior to January 1, 1922. 



Chapter III. Texts and legislative records of the eugenical sterilization laws. 



Chapter IV. Statistical and descriptive summary of eugenical sterilization in the several 

 States. 



Chapter V. Analysis of the eugenical sterilization laws by subject. 



Chapter VI. Analytical outline of litigation growing out of the several eugenical steriliza- 

 tion statutes previous to January 1, 1922. 



Chapter VII. Detailed review of litigation growing out of the several eugenical steriliza- 

 tion statutes. 



