DEPARTMENT OF GENETICS. 145 



Table 12. — Nativity ratios in the po'pulation {1910) and in institutions. 



1. Native, both parents native 



2. Native, one parent native-born, one parent 



foreign-born 



3. Native, both parents foreign-born 



Total native born (1, 2, and 3) 



4. Foreign-born 



Total foreign stock (2, 3, and 4) 



Total 



population 



of United 



States, 



1910. 



p. ct. 

 64.47 



6.60 

 14.23 



85.30 



14.70 

 35.53 



In 81 State 

 institutions, 

 Jan. 1, 1921. 



p. ct. 

 56.50 



8.23 

 15.29 



80.04 



19.90 

 43.49 



Ratio institu- 

 tion quotas to 

 institution 

 findings. 



100 : 87.63 



100 : 124.69 

 100 : 107.44 



100 : 93.83 



100 : 135.37 

 100 : 122.40 



is convenient in botany and zoology. It was found also that the 

 older schemes of classifying human handicap are being discarded, and 

 that as yet no new satisfactory systems have been evolved. The study 

 of this problem is being continued. 



Race Mixture. 



First-hand pedigree studies were made by Dr. Laughhn of the 

 family distribution of personal traits in a Hawaiian-Chinese-Irish 

 family of California. The traits considered were business thrift versus 

 thriftlessness, musical sense versus lack of musical appreciation, love of 

 the sea versus its lack, sound judgment versus its lack, quick temper 

 versus emotional control, enthusiasm versus its lack. It was found 

 that these traits (many of them racial) segregated and recombined 

 in a quite clean-cut manner. 



PHYSIOLOGY OF REPRODUCTION AND DEVELOPMENT. 

 Influence of Endocrine Glands of Mother on Variability of Offspring in Birds. 



Results obtained by Dr. Oscar Riddle during the present year 

 demonstrate in a striking manner the indispensable need for the asso- 

 ciation of studies on the physiology of reproduction with investigations 

 in genetics. First among these results is the discovery, made in col- 

 laboration with Mr. Embree R. Rose, of the physiological basis of a 

 series of reproductive abnormalities involving the early elimination by 

 death of numerous bird embryos. It has been definitely shown that 

 at least many of these reproductive abnormalities and embryonic 

 deaths are due to temporary or permanent insufficiency of the endo- 

 crine glands, particularly the thymus and parathyroids. Or, stated 

 in terms more accurately descriptive of the present state of this 

 investigation, the administration per os of the desiccated tissue of 

 these glands, either alone or in combination, is specific for the restora- 



