Purple-tailed Comet (Cometes? Glyceria), John Gould During the many years that I have given attention to the Trochilidæ, I have not met with a bird which has caused me more thought, and I may say perplexity, than the one represented on the accompanying Plate. This illustration has been restored to its original vibrancy by enhancing colors and removing unwanted marks. A monograph of the Trochilidæ, or family of humming-birds was published between 1849 and 1887 by English ornithologist John Gould. This monumental work depicts and describes all the known species of hummingbirds at the time - comprising 418 lithographic plates and information on 537 species."