562 EXPEEIMENT STATION RECOKD. 



speedily alleviated by the introduction of butter fat into the experimental 

 rations. 



" The chemical character of the unique * accessory substance ' in butter fat 

 must be investigated in detail and its possible presence elsewhere determined. 

 Experiments are already under way with varying proportions of butter fat in 

 the ration ; but we have not thus far determined the necessary allowance. On 

 the other hand, no amount of butter fat will induce growth on certain dietaries 

 in which the proportions and nature of the inorganic salts are inappropriate 

 . . . , or the quantity and character of the protein are inadequate." 



In a supplementary note brief reference is made to experiments undertaken 

 to determine the possible efficiency of fats other than butter fat in preventing 

 decline on the protein-free milk food used and promoting growth. Marked 

 differences in fats from different sources have been found. Egg yolk, for ex- 

 ample, appears to behave like butter fat, while some other fats have thus far 

 proved no more efficient than lard. 



" Such considerations make it evident that the comparative value of the 

 natural fats employed in nutrition must be determined, as well as the in- 

 dividual role of the different proteins, carbohydrates, and mineral nutrients." 



Metabolism of mineral matters, R. Berg (Pharm. Zentralhalle, 5Jf (1913), 

 No. 47, pp. 1212-1216). — From clinical observations and theoretical considera- 

 tions, and on the basis of extensive analysis of the mineral content of various 

 food materials (E. S. B., 29, p. 366), the author formulates the principle that 

 a healthful and adequate diet must contain sufficient inorganic bases to neu- 

 tralize the inorganic acids present in the food or formed during metabolism, 

 and indicates food materials which may be advantageously used to accomplish 

 this result. 



Metabolism of fasting infants, A. Schlossmann and H. Murschhauseb 

 {Biochem. Ztschr., 56 (1913), No. 5-6, pp. 355-415, figs. i2).— Infants accus- 

 tomed to bottle feeding were given water sweetened with saccharin in the place 

 of their usual food for periods of from 80 to 76 hours, and the effects on body 

 changes, and, in a few cases, on respiration were noted. The data for nitrogen 

 metabolism and acetone and /3-oxybutyric acid are given in detail, but no general 

 conclusions were drawn. 



Investigations of the presence and distribution of manganese in animal 

 organs, G. Bertrand and F. Medigreceanu (Ann. Inst. Pasteur, 21 (1913), 

 No. 1, pp. 1-11; al)S. in Hyg. Rundschau, 23 {1913), No. 22, p. i^^-?)-— Small 

 quantities of manganese (1^ to ^ mg. per 100 gm. fresh material) were 

 found in all the organs and secretions of the 15 types of vertebrates examined, 

 except in the whites of birds' eggs. The differences in the proportions of 

 manganese found in different parts of the same animal were greater than in 

 the same organs of different animals. In general, manganese was more abun- 

 dant in birds than in mammals, and in liver, kidneys, hair, nails, and feathers, 

 than in lung, nerve tissues, milk, and blood. 



Investigations of the amount of manganese normally present in the 

 blood, G. Bertrand and F. Medigreceanu {Ann. Inst. Pasteur, 26 {1912), 

 No. 12, pp. 1013-1029; ahs. in Hyg. Rundschau, 23 {1913), No. 22, pp. 141O, 

 141I). — In spite of accurate methods, the results of these studies according to 

 the authors do not agree with those of previous investigators, but indicate 

 much smaller quantities of manganese. 



In normal human blood, as well as that of various domestic animals and 

 birds, only from iAj to -^ mg. or less of manganese was found per liter. Twice 

 as much was present in the red blood corpuscles as in the plasma. 



The influence of manganese on metabolism is to be studied in future work. 



