Among the reeds and rushes that border quiet streams and ponds lives Hydrometra lineata, one of the least known of our North American Hemiptera. This insect is comparatively rare in collections, but common enough in nature, though owing to its small size and inconspicuous appearance it escapes all but the sharpest-eyed collectors. Its elongate body is borne on hairlike legs and resembles a bit of twig or grass more than a living insect. After the eye becomes accustomed to the odd shape, they are most easily distinguished, especially when they move about over the surface of the water. During the past summer I took over five hundred specimens of this insect without any special effort, finding them common through New York State, Massachusetts, and Connecticut.