1918. With thirty-two black and white illustrations. Contents: Animals that Practise Camouflage; Animal Musicians; Animals at Play; Armour-Bearing and Mail-Clad Animals; Miners and Excavators; Animal Mathematicians; The Language of Animals; In their Boudoirs, Hospitals and Churches; Self-Defense and Home-Government; Architects, Engineers, and Housebuilders; Food Conservers; Tourists and Sight-Seers; Animal Scavengers and Criminals; As the Allies of Man; and The Future Life of Animals.