270 



POSTNATAL GROWTH OF HEART, KIDNEYS, LIVER, AND SPLEEN. 



SUMMARY. 



Each organ has a period of rapid growth soon after birth, a second period 

 from 2 to 8 years, and a third period about puberty. Each of these periods alter- 

 nates with one of slow growth. As growth proceeds each organ becomes either 

 large or small, depending upon the type of individual. There are changes in size 

 due to the state of nourishment and to pathological conditions; race and sex also 

 influence the size of the organs. The most characteristic racial difference is found 

 in the spleen, which is larger in the white than in the negro. 



The rate of growth is determined from the weight of the organ preceding the 

 period of growth under consideration; that for the first 2 years is based upon 

 the weight of the organ at birth; the other periods begin at 2, 10, and 18 years 

 respectively. 



The growth of the heart is slower during the first two years than is that of 

 the spleen, liver, or kidneys; but after that time, until maturity is reached, the 

 rapidity of its growth is relatively greater than that of the other organs. During 

 the periods after the second year the kidneys grow relatively less than the spleen, 

 and the spleen relatively less than the liver. 



In conclusion, attention is called to the great importance of collecting and 

 carefully studying material about which the following data may be ascertained: 

 Age, sex, race, type, relation to puberty, antecedent habits, heredity, condition of 

 nourishment, pathological condition, and the actual cause and condition of death. 

 The type and the relation to puberty are especially important, and it may be 

 helpful to obtain the largest possible number of cases of instantaneous death. 

 This will necessitate, of course, the cooperation of a large number of observers 

 at different places and over considerable periods of time. The interest that has 

 already quickened into activity, however, bids fair to result in better records for 

 the future. 



BIBLIOGRAPHY. 



BARDEEN, C. R., 1918. Determination of the size of the 



heart by means of the X rays. Amer. Jour. 



Anat., vol. 23. 

 BEAN, R. B., 1912. Morbidity and morphology. Johns 



Hosp. Bull., vol. 23, No. 262. 

 , 1914. The stature and the eruption of the per- 



mament teeth of American, German-American 



and Filipino children. Amer. Jour. Anat., vol. 17. 

 GODIN, PAUL, 1903. Recherches Anthropomfitritmes sur 



la croissance des diverses parties du corps. 



(Prix Broca). 

 , 1910o. Les proportions du corps pendant la 



croissance. Bull, et M<Sm. de la Soc. d'Anthrop. 



de Paris. 

 , 19106. Alternances des accroissements au cours 



du developpement du corps humain. Comp. 



rend. Soc. de Biol., vol. 68, p. 1119-1121. 

 , 1911. Essai d'explication du role de la pubert 



chez 1'homme. Bull, et Mm. de la Soc. d'An- 

 throp. de Paris. 



GODIN, PAUL, 1913. La croissance pendant 1'agescolaire. 



Delachaux et NiestlS, Neuchatel. 

 , 1914. Comment s'accroit notre corps de la 



naissance a 1'age adulte. Croissance, vol. 1, 



No. 5. 

 KRESS, E., 1902. Ueber Organgewicht bei Kindern. 



Diss., Munich. 

 LAPICQUE, Louis, 1907. Tableau gne>al des poids soma- 



tique et encphalique dans les especes animales. 



Bull, et M6m. de la Soc. d'Anthrop. de Paris, 



No. 3. 

 MALL, F. P., 1918. On the age of human embryos. 



Amer. Jour. Anat., vol. 23. 

 MANOUVRIER, L., 1902. M6moires de la Socie'te' d'An- 



thropologie de Paris, tome 2 (3e serie), 3e fasc., 



p. 98-101. 

 VIERORDT, H., 1907. Daten und Tabellen, Anatomische, 



Physiologische und Physicalische. Gustav Fis- 

 cher, Jena. 



