Slide showing two diagrams of hen-feathered males, one who has been castrated, one who has not. Slide shows two diagrams of hen-feathered males, one who has been castrated, one who has not. Title below diagrams reads: 'Plate IV. - Results of castrating hen-feathered males in Sebright Bantams: a, normal male; b, castrated male. (After Morgan by permission of the Carnegie Institution of Washington).' The words 'Facing page 556' also appear in the bottom right corner of the slide. Late 19th to early 20th century