Abortion, [93], [118]

Accidents to children, [136]

Acquired immunity, [86]. See also [Regeneration]

Adoption, [90], [117]

Advice to mothers, [65], [134]

Age of parents, [80], [81]

— productive and unproductive, [12]

— pyramid, [12], [13]

Agricultural colonies, [146]

— schools, [214]