Goodrich: An Office-Holding Family 



283 



strata of the population, could be found 

 in which the members were marked by 

 general physical, mental, and moral 

 soundness, and by a spirit of public 

 service rather than merely by one of 

 money-gettin.cj, it ought to be possible 



to promote the fertility of such families 

 by eugenic measures. 



It is with the hope of stimulating 

 genealogists to work from the point of 

 view of civic worth, that the present 

 paper is published. 



THE INHERITANCE OF ARITHMETICAL ABILITIES 



IT IvS no longer possible to doubt that 

 mental capacities are inherited, but 

 the analysis of them is extremely 

 difficult. Does a child inherit gen- 

 eral arithmetical ability, for example, 

 or is ability in subtraction different 

 from ability in addition; or are all sorts 

 of arithmetical ability merely due to 

 the amount of training given to some 

 more general form of intellectual capac- 

 ity? Margaret V. Cobb has been 

 studying this particular problem, and 

 presents a preliminary report in the 

 Journal of Educational Psychology fviii, 

 pp. 1-20, January, 1917). 



The abilities she considers are addi- 

 tion, subtraction, multiplication, divi- 

 sion, and speed in copying a column of 

 figures. 



"The measurements made show that 

 if, for instance, a child is much quicker 

 than the average in subtraction, but 

 not in addition, multiplication or 

 division, it is to be expected that one 

 at least of his parents shows a like trait; 

 or if he falls below the average in 

 subtraction and multiplication, and 

 exceeds it in addition and division. 



again the same will hold true of at 

 least one of his parents. ' ' These various 

 kinds of arithmetic appear to be 

 dependent on different functions of the 

 brain, and are therefore probably in- 

 herited independently, if they are 

 inherited at all. Furthermore, the 

 inheritance must be segregating. All 

 the children of the same family do not 

 always resemble the same parent. 



To assume that the resemblance 

 between parent and offspring in arith- 

 metical ability is due to association, 

 training and imitation, is not plausible. 

 If this were the case, a class of children 

 ought to come to resemble their teacher, 

 but they do not. Moreover, the child 

 sometimes resembles more closely the 

 parent with whom he has been least 

 associated in daily life. 



The details of Miss Cobb's study, 

 which was made by means of correla- 

 tions, cannot be convenienth' sum- 

 marized. They seem, however, to bear 

 out her conclusion that heredity plays 

 at least a considerable part in determin- 

 ing a child's ability at various arith- 

 metical processes. 



Lectures on Heredity in Washington 



A course of three lectures on heredit}- 

 was given by the Washington Academy 

 of Sciences this spring, as follows : 



Prof. H. S. Jennings of Johns Hopkins 

 University: Ohserved changes in hered- 

 ity characters in relation to evolution. 

 March 15. 



Dr. Oscar Riddle, Carnegie Institu- 

 tion (Cold Spring Harbor, L. I.): The 



control of the sex ratio. March 29. 



Prof. W. E. Castle, Bussey Institu- 

 tion, Harvard University: The role of 

 selection in heredity. April 13. 



These lectures are published in the 

 Proceedings of the Washington Academy 

 of Sciences, and can be obtained .sepa- 

 rately. Dr. Frederick Wright is secre- 

 tarv of the Academv. 



