EUGENICS RECORD OFFICE. 147 



pleasure to do those things for the doing of which well we have special 

 gifts. Attempts to do things for which we have no natural aptitude 

 are distasteful; but we like to do the things that we can do well; and 

 we can do well, after a little training, things for the doing of which 

 we have natural aptitudes. So we like to do the things for which we 

 have natural aptitudes. 



These conclusions are supported by the work on ''Naval Officers, 

 their Heredity and Development," prepared by the Director, with the 

 assistance of Miss Mary F. Scudder, and published by the Institution. 

 This study shows that naval fighters are chiefly hyperkinetics (over- 

 active). In their youth they were nomadic, thalassophihc, adventur- 

 ous. Other naval officers were such because they were great strate- 

 gists (like St. Vincent), administrators (like Stockton), explorers (like 

 Sir John Franklin), and adventurers (Uke William B. Gushing), 

 Each type has its prevailing temperamental and intellectual equip- 

 ment. Each officer, as a boy, gave promise of his adult performance. 

 One of the most widespread traits among naval officers is love of the 

 sea (thalassophilia) . This is an inherited racial trait, a fundamental 

 instinct. In inheritance it acts hke a recessive that is also sex-limited, 

 so that it shows itself almost exclusively in males. Another trait of 

 fighting naval officers is, as just stated, hyperkinesis, a dominant trait. 

 Still a third is nomadism, a sex-Unked trait. Thus, the total inherit- 

 ance of great naval fighters and explorers is complex. 



INBRED COMMUNITIES. 



Another investigation that is under way is that of certain isolated 

 island communities, to learn the results of inbreeding in those com- 

 munities. Some years ago, Miss Mary M. Sturges spent 18 months, 

 at intervals, in one such locality and 6 months in another for compari- 

 son with the first. 



" In the first island a fairly complete genealogy was obtained of the descend- 

 ants of twelve children from a marriage dating 1800, with ancestral and 

 collateral lines so determined that relationships are quite accurately known. 

 A rougher, although fair, genealogy was obtained in the second island, and an 

 endeavor was made to furnish each with a good historic and descriptive setting. 



"Since consanguineous marriages subsequent to 1825 have formed 48 per 

 cent (first-cousin marriage 11 per cent) of all, so many ancestors were common 

 that direct and collateral branches could be unusually well known. Thus, 

 aside from a useful addition to our knowledge of the sociological elements of 

 isolation and inbreeding, the material affords by comparison of branches and 

 location of traits in inheritance a background for such intensive work as may 

 seem desirable. By means of such comparison and one rough census of 6 of the 

 12 complete branches (2 parallel first-cousin marriages, 4 parallel marriages 

 of a set of brothers with a set of sisters), certain traits have been roughly 

 located and the two months this summer have been spent in tabulating them ; 

 the incidence of left-handedness; red hair; albinism, asthma, hayfever, 

 eczema, and angioneurotic edema; twinning; congenital anomaHes, single or 



