PART III. FAMILY STl DIES l\ HEREDITY OF I'.l III). 



A. STATEMENT OF PROBLEM. 



Our study of the mass relation in build between parental and filial 

 generation has followed the ordinary pre-Mendelian method of analy- 

 sis of heredity, a method that has proved rather sterile for prediction 

 of filial traits. It has, however, enabled us to formulate an hyp* >th< 

 in Mendelian language. It now remains to use our data in Mendelian 

 fashion, to seek a test of the hypothesis. 



In this study we shall not use all of the families Listed in tie' mam 

 tables of the Appendix, because some of them are for various reasons 

 not adequate for Mendelian analysis; for example, in some cases the 

 ancestry is insufficiently known, so that the gametic nature of the 

 parents can not be inferred. It is considered preferable to analyze a 

 few of the more completely known families than to rest content with 

 the mass statistics. I shall take up in order the more significant 

 matings. 



B. DISCUSSION OF SPECIAL MATINGS. 



Class I. Both Parents Slendi b. 

 Mating 1. One Parent Is Very Slender, of Slender St<x k. tiik Otheb Slenoeb. 



We have only two fair cases falling into this category. The 

 *Fun family with the paternal formula 27. 29, 27 and the maternal 

 formula 32, 27, 25; and the Sch-37 family with the paternal formula 

 29, 33±, 29 and the maternal formula 27±, 29± ftb, 25. I In these 

 formulas the indices of father's father, father's mother, father, and 

 similarly for the mother's side of the house are given in that order.) 

 The full history of these cases follows: 



*Fun Family. (Fig. 22. i 



II 6. 6 , 170 cm. (67 inches) tall, and weighing 56 kg. 1 123 pounds) ; build 

 1.9 (27) ; slender and of exclusively slender sibship and parentage; married 

 II 7, 5 , 167 cm. (66 inches i tall and weighing 50 kg. (110 pounds I ; build, 

 1.8 (25); very slender and of slender or medium sibship and parent 

 They have 2 children: (1) $ , at 27 years, 16.) cm. (66 inches) tall and 

 weighing 54 kg. (118 pounds); build 1.9 (28), slender; (2) . at 24 yi 

 183 cm. (72 inches) tall and weighing 68 kg. (149 pounds), build 2' 

 slender. 



Thus this mating of very slender X slender parents yielded only 



(2) slender offspring. A slender X slender mating from the -ame 

 family may be added here. 



♦The aateri.sk immediately preceding the reference letter* means <. ; i 

 to is not included in the statistics of table 11. 



t tb or f t. immediately following an index Dumber in tbjs Study • signifies tli I with 



that index number had active tuberculosis. The t U leath by the 



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