An American text-book of physiology . 1284123812451256134i>12381273123713251234122813201283127812491224 38 11 28 23 13 19 10 8 9 1 4 1 2 3 5 8 15 18 21 15 33 31 16 26 33 33 Total number of cases, 415. Total number of cases, 424. From the same figures the first part of the accompanying curve (Fig. 204)has been formed. The curve beyond the twenty-fifth year is continued on the basis of theobservations by Bischoff,^ and for comparison the curve representing theencephalic Aveights of a series of eminent men, forty-five in number, is drawnin a dotted line, the averages for decennial periods bein
An American text-book of physiology . 1284123812451256134i>12381273123713251234122813201283127812491224 38 11 28 23 13 19 10 8 9 1 4 1 2 3 5 8 15 18 21 15 33 31 16 26 33 33 Total number of cases, 415. Total number of cases, 424. From the same figures the first part of the accompanying curve (Fig. 204)has been formed. The curve beyond the twenty-fifth year is continued on the basis of theobservations by Bischoff,^ and for comparison the curve representing theencephalic Aveights of a series of eminent men, forty-five in number, is drawnin a dotted line, the averages for decennial periods being alone plotted. These records exhibit the fact that at birth the weight of the brain is aboutone-third of that which it will attain at maturity. The increase is very rapidduring the first year, and vigorous for the first seven or eight years, after whichit becomes comparatively slow. The maximum weight is indicated in the ^ Archiv fiir Anatomie und Physiologie, 1890. * Himgewicht des Menschen, Bonn, 1880. CENTRAL NERVOUS SYSTEM. 725. Fig 2( for each sex, showing the weight of the brain according to age. For the firsttwentv-five years the curve is formed from annual averages based on the figures of H. Vierordt; fromtwenty-five years on the curves are formed from decennial averages based on the observations ofBischoff. All the data are from observations on the less fortunate classes. The dotted curve for emi-nent men is formed from decennial averages based on forty-five observations. fifth decade (males), fourth (females), although there is a premaximum in themiddle of the second decade (at thirteen and fifteen years for males and four-teen vears for females), in which the too early and too vigorous growth of the •20 AN AMERICAN TEXT-BOOK OF PHYSIOLOGY. cncoplialon aj>i)cars to be an important factor in tho cause of death ; hence thelarger brain-weight Ibimd at autopsies during those years. Wiiile, in general,the individual may be supposed to follow in the developm
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