(1) Aèdes vigilax migrates for long distances and together with Mucidus alternans disperses over considerable areas under favourable physiological conditions.

(2) Migrations are only undertaken when suitable winds make dispersal possible ; north-westerly winds distribute, under suitable atmospheric conditions, untold numbers of A. vigilax all along our foreshores.

(3) In summer the appearance in large numbers of both A. vigilax and Mucidus alternans heralds the approach of a storm.

(4) The presence of mosquitos found in wide areas in Queensland apparently devoid of water may be explained : (a) By the existence of breeding facilities in tree-cavities and similar breeding-places not visible to a casual observer ; (b) by the prevalence of suitable carrying winds by which mosquitos are blown for short or long distances from their native breeding-places ; (c) by extreme localisation of mosquitos breeding in small quantities of water mostly inaccessible to the casual observer.