HISTORICAL RACES 243
(1) These races fall under four sub-headings. For all of them
the evidence is discussed concerning (2) disease, (3) warfare,
(4) and child mortality. (5) In sub-groups 1 and 2 celibacy and
postponement of marriage, (6) pre-puberty marriage, (7)
lactation, (8) restraint from intercourse, (9) contraceptive
practices, (10) size of family, (11) abortion, (12) and
infanticide. (13) In sub-groups 3 and 4 pre-puberty intercourse
and lactation, (14) celibacy and marriage, (15) contraceptive
practices, (16) abortion and infanticide, (17) and venereal
disease.