Mackerel and Sunshine

In his paper on "Plankton Studies in Eelation to the Western Mackerel Fishery," in the last number of this Journal (Vol. VIII., p. 269), G. E. Bullen shows that for the years 1903–1907 there appears to be a correlation between the number of mackerel taken during May and the amount of Copepod plankton, upon which the mackerel feed, taken in the neighbourhood of the mackerel fishing grounds during the same month.