THE EVOLUTION OF DEATH 



67 



developed as guinea-pigs, and much less far developed are 

 newborn rabbits. I have determined the rate of growth in 

 both of these animals, and found that chickens, as soon as 



3)2 13 ZZ 33 '1656 66 77 90 105 130 197 days SW 



Fig. 29. — Curve of the daily percentage increase in weight in male chickens. 



3'/: 13 22 33 ^6 5566 77 90 106 130 197 days 3^ 



Fig. 30. — Curve of the daily percentage increase in weight of female chickens. 



they have recovered from their hatching, may grow as much as 

 9 per cent, per day, which is much quicker than the guinea- 

 pigs grow. The values for the two sexes are practically equal. 



