MANNER OF DEVELOPMENT. 51 



It is no valid objection to this conclusion that animals sud- 

 denly supplied with an excess of food, or when grown very 

 fat, and that most plants on sudden removal from very 

 poor to very rich soil, are rendered more or less sterile. We 

 might, therefore, expect that civilized men, who in one 

 sense are highly domesticated, would be more prolific than 

 wild men. It is also probable that the increased fertility of 

 civilized nations would become, as with our domestic 

 animals, an inherited character : it is at least known that 

 with mankind a tendency to produce twins runs in families. * 

 Notwithstanding that savages appear to be less prolific 

 than civilized people, they would no doubt rapidly increase 

 if their numbers were not by some means rigidly kept down. 

 The Santali, or hill-tribes of India, have recently afforded 

 a good illustration of this fact; for, as shown by Mr. 

 Hunter, f they have increased at an extraordinary rate since 

 vaccination has been introduced, other pestilences mitigated, 

 and war sternly repressed. This increase, however, would 

 not have been possible had not these rude people spread 

 into the adjoining districts, and worked for hire. Savages 

 almost always marry ; yet there is some prudential restraint, 

 for they do not commonly marry at the earliest possible age. 

 The young men are often required to show that they can 

 support a wife ; and they generally have first to earn the 

 price with which to purchase her from her parents. With 

 savages the difficulty of obtaining subsistence occasionally 

 limits their number in a much more direct manner than 

 with civilized people, for all tribes periodically suffer from 

 severe famines. At such times savages are forced to devour 

 much bad food, and their health can hardly fail to be 

 injured. Many accounts have been published of their pro- 

 truding stomachs and emaciated limbs after and during 

 famines. They are then, also, compelled to wander much, 

 and, as I was assured in Australia, their infants perish in 

 large numbers. As famines are periodical, depending 

 chiefly on extreme seasons, all tribes must fluctuate in 

 number. They cannot steadily and regularly increase, as 

 there is no artificial increase in the supply of food. Sav- 

 ages, when hard pressed, encroach on each other's- terri- 

 tories, and war is the result ; but they are indeed almost 



*Mr. Sedgwick, "British and Foreign Medico-CMrurg. Review," 

 July, 1863, p. 170. 

 f " The Annals of Rural Bengal," by W. W. Hunter, 1868, p. 259. 



