Note 1475 — XI THE REGULATION OF NUMBERS AMONG HISTORICAL RACES
Reading edition
For evidence that the decrease in fertility is due to artificial restraint see Stevenson, J. R. S. S., vol. lxxxiii, p. 431. There are reasons for thinking that contraceptive methods play a smaller, and restraint from intercourse a larger, part than is generally supposed (see Dr. Greenwood’s remarks on the paper quoted above, p. 440, and also Dudfield, J. R. S. S., vol. lxxi, 1908, p. 25).