MINERAL METABOLISM 



321 



"decalcifying" of the casein improves the fat and mineral utilization in 

 such cases ( Bosworth, Bowditch and Gibliu; Bosworth and Bowditch; 

 Forbfs(<;) ;. GifFliorn). 



The mineral requirements of childhood and adolescence have been sub- 

 jected to metabolism studies by Herbst (a) and Jundelt with the following 

 results : 



In another 12-day study of two rapidly growing adolescent boys Herbst 

 (b) found a daily exchange per kilogram of body weight as follows: 



These values are of interest in showing the relation of CaO deposit to 

 bodily activity and the lack of any parallelism between CaO and X. 

 Hoppe-Seyler and v. Noorden have noticed increased CaO elimination 

 in bodily inactivity. 



Recent work has greatly extended our information regarding the cal- 

 cium of the blood. That calcium, though present in small amount, is 

 one of the important constituents of the blood because of its effect on co- 

 agulation and heart irritability, has long been acknowledged. We are in- 

 debted to Jariscu(&) for a review of previous work, the development of an 

 analytical method and analytical results. Previous investigators have 

 found 4.0 to 11.9 mg. CaO per 100 c.c. blood (using strictly chemical 

 methods), with variations for a given species as great as the difference 

 between various species. Semi-exact methods, devised by Blair Bell and 

 Wright, have resulted in such wide variations in findings when employed 

 by different investigators (Katzenellenbogen; Morley; Mullik) . that 

 these results will not be considered in the following summary. Jansen, 

 Yoit, Dhere and Grimme, and Demisted t and Rumpf agree in finding 

 a variation in blood calcium dependent on age and independent of sex. 

 At birth the infant's and mother's blood are about the same in Ca 



