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 26 FORM AXD HABIT: THE TAIL. Tliis singular habit is practiced by numerous species of Motmots, ranging from Mexico to Brazil. It is there- fore of undoubted age, and we can only speculate upon its use and origin. Young birds from the nest, reared Fig 11 — Central tail feathers of Motmot ( Womotus svbruffsceni), showing newly giown featlieis, (at the left) and lesults of self mflitted mutilation in confinement where they were isolated from others of their kind, trimmed their tail-feathers soon after they were grown.* The habit, therefore, is inherited, but the mutilation, although it has doubtless been practiced for countless generations, has not become inherent, unless we consider the constriction in the vane of the feather at the place where it is to be trimmed an indication of inheritance. The Motmot gesticulates with its tail in a remarkable manner, swinging it from side to side, so that it suggests the pendulum of a clock, or sweeping it about in circles with a movement which reminds one of a bandmaster flourishing his baton. We shall find in other species, also, that the tail, more than any other organ, is used to express emotion. Recall its twitching and wagging ; how it is nervously spread or "jetted," showing the white See Cherrie, The Auk (New York city), vol. ix, 1892, p. 323.