This paper substantiates many limits to the general thesis which Louise Dulude has popularized under the title: “Old Age: a Women's World”. Using old age sex ratio as an indicator, the author shows that Canada's senior population has been mostly male until recently and still keeps that majority in rural areas and agricultural milieus; one country out of six in the world today and half of 18 main ethnic groups in Ontario in 1971 were mostly male at that age.

It is concluded that one sex prevailing on the other in old age is influenced by many factors: biology, history, migrations, ethnicity, milieu (rural urban) and types of activities.

A life table was constructed for the mustard aphid, L. erysimi during January, February and March corresponding to 14 ± 2°C, 16 ± 2°C, 20 ± 2°C and 74 ± 5%, 74 ± 6% and 54 ± 5% R. H. under laboratory conditions. The study revealed that the values of intrinsic rate of natural increase (rm) and finite rate of increase (λ;) were 0.1035, 0.096, 0.023 and 1.109, 1.101, 1.023 females/female/day. The doubling time (DT) was higher in the case of alate morph during March (13.088 days) than apterous morph during January (6.697 days) and February (7.220 days). On reaching the population at a stable age distribution, the nymphal population estimated was 84.36, 93.87 and 92.67 in January, February and March respectively. The life expectancy (ex) of newly born nymphs of L. erysimi declines monotonically with advancing of age in these months.