480 



SGIEN'CE. 



[Vol. VI., No. 147. 



maminals. In a general way there is an inverse 

 relation between the number of offspring and the 

 size of the animal. (This may indicate why many 

 of the mammoths are extinct.) While the lower 

 species is more productive, the life of the indi- 

 vidual is much shorter. This inverse ratio 

 between the productiveness of the species anfl 

 the longevity of the individual is a very fortunate 

 arrangement ; for, according to the estimation of 

 M. Quatrefages, two successive generations of the 

 offspring of a single plant-louse would cover eight 

 acres, and the fish would fill the sea in a man's 

 lifetime. Again : in the lower organisms the mor- 

 tality is great ; very many die before reachiag 

 maturity. 



Inferior races are more prolific than superior 

 races. The finest varieties of fruits bear least. 

 Dog-fanciers testify that the most intelligent 

 varieties have the fewest young ones. In man 

 the lower races ^ are most productive. Among the 

 Kafirs twins are said to be as common as single 

 births, and triplets frequently occur. The black 

 race is more fertile than the white. One authority 

 gives 2.05 children for each white woman, and 

 2.42 for the colored. The Chinese occupy less 

 than 1-300 of the surface of the globe, and yet 

 their population includes nearly 1-3 of the human 

 race. Among European nations, Eussia and Spain 

 are the most productive, Switzerland and France 

 the least. 



The inference to be drawn is not that in France 

 the duties of maternity are shirked, but that the 

 natural effect of a high civilization shows itself in 

 this diminution of fertility. Nor is it a mark of 

 decadence, for the Swiss nation shows a similar 

 phenomenon. Again : while Spain and Italy show 

 a higher productiveness, the longevity is lower. 

 The average life is thirty-one years : in France it 

 is forty years. France has more persons from 

 fifty to sixty years of age than other countries. 

 What is lost in quantity is gained in quality. The 

 number of children per marriage has been de- 

 clining : from 1800 to 1815 it was 3.9; 1815 to 

 1830, 3.73 ; 1874 to 1878, 3.04 : but the mean life 

 has increased. Fi'om 1810 to 1815 it was 31 years 

 3 months ; 1820 to 1830, 32 years 2 months ; 1861 

 to 1865, 37 years 6 months. In other countries of 

 advanced civilization, the fertility, though still 

 high, is on the decrease. England, Austi*ia, 

 Prussia, — all show the same state of affairs. These 

 countries wiU in time exliibit the same loss of 

 fecundity as is shown in France now. An ad- 

 ditional refutation of the charge of the voluntary 

 origin of this sterihty is the fact that the ratio 



1 The Hottentots, Fuegians, etc., are really no excep- 

 tions, as these races are starved, and naturally tend to 

 extinction. 



of marriages to the population has not been de- 

 creasing in France, and is now as high as else- 

 where. 



The young are more fertile than the old. Young 

 vines give a large harvest, but the grapes are poor. 

 Buff on states that at 18 women are more produc- 

 tive than at 30 ; according to an English authority, 

 fertility increases up to 25 or 30 years, and then 

 diminishes. To-day the French woman is 24i 

 years old, the man 29 years 7 months, at the time 

 of marriage. In the eighteenth century they 

 were 19 and 25 years respectively. The result is 

 that to-day the fertility is less ; but the quality of 

 the offspring is better. 



Witliin certain limits a weak temperament 

 favors fertihty. Domesticated animals have more 

 offspring than wild ones. A vigorous active life 

 apparently does not favor longevity. Tailors and 

 shoemakers have more children than blacksmiths. 

 The ancient atliletes and the modern acrobats 

 seldom have children. War kills off the strongest 

 men, and leaves the weak to propagate the race ; 

 hence the birth-rate increases. From 1811 to 1815 

 it was 3.49, but from 1816 to 1820 it was 4.08 m 

 France. 



Brain-workers and intelligent people have fewer 

 children than others. Sixty-one married pro- 

 fessors of the medical faculties of Paris, Lyons, 

 and Bordeaux, had only 1.78 children to each 

 marriage. The mortahty among these cMldren, 

 however, was very low ; and so, in general, the 

 offspring of these more evolved, less fertile classes 

 is of a stronger, larger, and higher kind. Fortes 

 creantur a fortibus. 



There probably is a limit below which propa- 

 gation is impossible ; but there is surely a limit of 

 too high nurture, above which reproduction is 

 lowered ; and the maximum fecundity is a state 

 nearer to the want than to the excess of good 

 nurture. 



In the more advanced races a famine increases 

 the birth-rate. The poor are notoriously prohfic 

 of offspring. But the offspring of the wealthy 

 classes is longer lived. Finally, as to climate : 

 the fertihty is higher in warm countries, but 

 the mortality is lower in the north than in the 

 south. 



Productiveness is a characteristic of the lower 

 species and races ; of the younger individuals ; of 

 the weak, both bodily and mentally. There is 

 throughout an inverse relation between quality 

 and quantity of offspring. AU circumstances 

 that modify fecundity in plants and animals 

 are equally active m man, and hence in the 

 French people as well. The diminution in fertility 

 observable in other European nations as well as in 

 the French is a physiological and not an economic 



