THE BACK CRO \\\ 



cent of the intermediate and 50 per cent of the n .<•. Wh. a 

 3 multiple factors are present and lie' heterozygote is Dearly inti 

 mediate but shows a slighl tendency toward imperfect dominai 



may expect an approximation to a symmetrica] distribution of 

 about the intermediate condition, with a skewness toward the !•• 

 sive condition. That is what is got in both parts of table ::_'. I 

 result supports the conclusion that there is segregation in the garni 

 of the heterozygous parent, so that the progeny tend prevailingly 

 fall again into the slender and medium-fleshy grandparental 

 The results of table 33 similarly support the conclusion of a i ion 



in the gametes of the heterozygous fleshy parent. 



C. GENERAL DISCUSSION 



Heredity and Environ. mi n i in Hi n.n. 



That a tendency to slenderness or fleshiness of build "runs in 



families" and characterizes different races is a mat tor of < unon 



observation. But this fact is far from satisfying the clinician that 

 heredity plays any part in this result. Thus, von Noorden, who 

 occupies a leading position among Teutonic investigators of metab- 

 olism in general and obesity in particular, denies the importance of an 

 hereditary anomaly of metabolism in different families and ia 

 Rejecting "anomaly of metabolism" or "peculiarity of protoplasmic 

 metabolism," he stresses "inheritance" of habits of life that favor 

 obesity, the quantity and quality of food, and the ideals of bodily 

 activity. For example, the Eskimo are fat because they 

 blubber and huddle in narrow spaces, undergoing little movement 

 throughout the long, dark winters. It is true that von Noorden 

 speaks somewhat guardedly; he recognizes exceptions; - 

 possible hereditary hypofunction of the thyroid. But clearly consti- 

 tutional peculiarities are, for him, exceptional as causes of <> 

 weight, and here is where he fails to recognize sufficiently tl. 

 that usually only particular individuals of a fraternity ate fleshy; 

 the others may be slender. 



But besides anomalies of protoplasm and family tradition- 

 feeding, there are obviously other possibilities. It is well known that 

 different varieties of cattle differ greatly in their capacity for fatten- 

 ing. Armsby and Fries (1911) have inquired into tin- influence 

 type upon the fattening of cattle. They used a pure-bred Aberd< 

 Angus steer and a "scrub," part Jersey, Bteer for comparison. \- 

 well known, the former belongs to the easily fattening beef ty] 

 the Jersey to the difficultly fattening milk type. During 

 years, beginning at under 1 year of age, these steer- were un<: ily 



continuous observations. They were fed on ordinary growing rati. 



