114 



AGE, GROWTH, AND DEATH 



we can prove the same phenomena with slightly dif- 

 ferent values. Girls, like the females of other species, 

 grow a little less forcibly (Fig. 39) than boys. They 

 do not quite attain a 200 per cent, value for the first 

 year, but they too drop in a similar manner to the boys 

 to about 30 per cent., and away down towards 10 per 



100% 



3 A 5 6 7 8 9 10 II 12 13 14 15 16 17 18 19 20 21 22 23 



cent, in the third year. Then comes the long slow 

 gradual decline up to the period of twenty-three. Pro- 

 fessor Donaldson, as our next slide will demonstrate 

 to us, has prepared curves (Fig. 40) from the English 



