On the back of each of the rings of the abdomen, or hindmost division of the body, of the Anopheles larvæ may be made out a pair of structures formed like minute palm leaves, the function of which appears to be that of keeping the little creature flush with the surface of the water. One of these larvæ, magnified about twenty times, with these structures and certain peculiar hairs on the front of the head, which are of value in distinguishing one species from another, more highly magnified, is figured on the preceding page. By the aid of these illustrations the reader should have no difficulty in recognising these organisms when he meets with them. When disturbed, they dart backwards and seek refuge among the _débris_ at the bottom, but cannot remain there long, and soon resume their resting position on the surface. The larvæ of many species are said to be carnivorous, and even cannibalistic, though I cannot say I have ever observed this personally, and in any case their main provision is found in the minute vegetable organisms which are abundant in the sites where they are common; the Culicine larvæ confining themselves mainly to those that are found completely immersed, while the young Anopheles browses on those floating on the surface, keeping its head screwed round, a full half-turn, so as to bring the mouth uppermost. The abrupt way in which this action is performed and reversed is extremely quaint, so that, as a writer remarks, one is rather surprised at its not being accompanied by an audible click.