106 H. Victor Parker, et al. 



29 per cent of total body water in the newborn baby to 51 per 

 cent of total body water in the adult and he stressed that an 

 increase in total muscular tissue rich in intracellular phase was 

 a prominent feature in the alterations in body composition 

 during growth. 



Yannet and Darrow (1938) found in their studies of cats a 

 relative increase in intracellular phase during growth in 

 muscles, whereas only very small alterations appeared in 

 liver tissue or in brain tissue. In studies of growing chickens 

 Barlow and Manery (1954) reported a similar relative increase 

 in the intracellular phase in muscular tissue. 



It appears from these studies that the alterations measured 

 with the dilution methods must be results of a development 

 varying quantitatively and qualitatively from one tissue to 

 another. 



In conclusion the alterations in body composition during 

 growth can be described as a disproportional increase in total 

 body solids, total body water, extracellular water, and intra- 

 cellular water. When the values are related to body weight 

 the following trends are seen during growth: a decrease in 

 total body water, an increase in total body solids, a decrease 

 in extracellular water, and a relative constancy in intracellular 

 water. When the water compartments are related to total 

 body water the trend is for a relative decrease in extracellular 

 water and a relative increase in intracellular water. 



Maturity 



The body water compartments in adults will be described 

 with particular reference to the sex difference. 



The material presented comprises ten normal males and 

 ten normal females at ages from 23 to 54 years, average age 

 in the middle thirties. The series was studied by H. V. 

 Parker in Dr. Francis D. Moore's laboratory, Peter Bent 

 Brigham Hospital, Boston (McMurrey et al., 1958). The 

 methods applied were : total body water was determined with 

 deuterium oxide ; the extracellular water was measured as the 

 radiobromide space, which was corrected for red cell bromide. 



