Chart B.—Showing Death-rates per 10,000 of the Population in Age-groups.

Age. —From this table it will be seen that, ignoring the three deaths over ninety-five years,.the highest death-rate was among persons between thirty and thirty-five. Of the total deaths 2,719 — or almost half—were among persons between the ages of twenty-five and forty, though only 24 per cent of the population are between those ages. In the Featherston Training-camp an analysis of over 2,000 hospital cases showed that, though men of from twenty to twenty-five yielded a high proportion of cases, the death-rate amongst such cases was proportionately less than among those of twenty-five to forty. Pneumonic complications arose in B'B per cent, of the cases among men under twenty-five, and in 12 per cent, of cases among men from twenty-five to forty. The younger men were perhaps equally susceptible to influenza, but were not equally liable to pneumonic complications, and, where such complications developed, were more able to combat the effects. Thus, taking the more serious pneumonic cases the young men showed a, case death-rate of 57 per cent., wliile among the older men the rate rose to 72 per cent. Table XI shows that under twenty the death-rate is very low, especially between the ages of five and fifteen. After forty the death-rate again declines until the more advanced ages are reached. The figures among the aged are rather too small to yield reliable data, but tend to show an increasing mortality again. The United States Public Health Report for the 14th March, 1919, makes an analysis of 13,000 cases of influenza which occurred in Maryland during the epidemic period. Discussing the influence of age the following comment may be quoted : — "The death-rate of influenza according to age is not an indication of the case incidence; while the incidence rate is highest among children of five to fourteen, and drops off in the older ages, the death-rate is quite low among children of these ages, and is markedly high among adults of twenty to forty-four, and among adults of advanced ages, although the number of persons in the advanced ages is relatively small." This observation certainly applies to the death-rate in New Zealand, as shown in Table XIII and to the limited observations made among the soldiers at Featherston Camp. Sex. —That influenza was a more fatal disease among males than among females is evident from the Government, Statistician's return in Table XIII; the death-rate per 10,000 among the former being 6496, as against 3488 in the latter. It is interesting to note, however, that among children under fifteen years of age the proportion of deaths was slightly higher for females than for males, while in ages above fifty years there is a tendency towards an increased proportion for females. In the figures for Maryland, quoted above, the same higher death-rate for males is seen, and the same tendency for the female death-rate below twenty and above fifty years to equal or surpass the male rate. A suggested explanation is that adult males are more exposed to unfavourable conditions than females in their conditions of work and living. This would not apply to children and those of advanced years, hence the disparity in death-rate disappears. Chart 15 graphically displays the variation and mortality due to se.x and age. It will be noticed that there is a marked rise in the female death-rate between the ages of fifty and fifty-five, dropping to the normal curve between fifty-five and sixty. Possibly this is merely a chance variant, a result of dealing with small figures. Race. —From the fact that 1,130 deaths out of 6,600 should have occurred among Natives, who represent under five per cent, of the total population, it is evident that the Maoris were exceptionally liable to attack by influenza in the more fatal forms. A similar susceptibility among Native races has been the universal experience. I have already quoted the case mortality in South Africa, which for Natives was double that of Europeans; and from the reports of the spread of the pan-

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