COMETES? GLYCERIA, Gowa. Purple-tailed Comet. Cometes Mossai, Gould, in Athenzeum, Sept. 24, 1853.—Ib. Report of Brit. Assoc. 1858, p. 68. Lesbia glyceria, Bonap. Rev. et Mag. de Zool. 1854, p. 252. Durie the many years that I have given attention to the Trochilide, 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. In point of affinity it is intimately allied to the members of the genera Leshia, Cometes and Cynanthus, par- taking as it does, either in form or colouring, of characters pertaining to each of those genera. Sometimes it has occurred to me that it might be a hybrid between either two of them, but I am perfectly at a loss to say which two species would be likely to produce such a cross. Such an idea has entered my mind, but when I have again and again reconsidered the matter, it has appeared to me that it is a distinct species, and that it may ultimately prove to be the female or young male of some gorgeous bird with which we are at present unacquainted. The only example known, and which is in my own collection, was procured by M. Mossa, near Popayan in Columbia, and by him sent to M. Parzudaki of Paris, from whom I obtained it. I regret to find that some confusion exists with regard to the specific name of this fine bird. Aware of its interest in a scientific point of view, I exhibited the specimen to the Natural History Section of the British Association for the Advancement of Science, at their meeting in Hull in 1853, and suggested the name of Mossai as its specific appellation ; but in an after-conversation, my friend the late Prince Charles Lucien Bonaparte advised me to give it the name of Gilyceria as being a more appropriate name for so beautiful a bird, and this name having appeared in the Prince’s and other lists of the family prior to the publication of the British Association Report, it is the one which must be adopted. M. Mossa being thus deprived of the compliment I had intended him, I beg here to testify to the value of his discovery, and to record my sense of M. Parzudaki’s kindness in giving me the first offer of so fine a bird. On aie tip of the hind-claw, I find a hard, agglutinated, wax-like mass which is irremoveable ; as I have seen nothing like it in any other member of the family, I have thought it only right to mention it. Head, back of the neck, wing-coverts, back and tail-coverts deep shining green ; wings purplish brown ; chin and throat metallic light olive-green ; sides of neck and under surface buff, _ a spot of deep shining green on the tip of each feather; tail dark reddish purple, passing into deep bluish green at the tip, cee on the outer feathers, where the hue is so faint as to be scarcely perceptible ; the outer feathers also have the basal three-fourths of the shafts and the outer webs buffy white, the base of the shaft paler than the web; basal three-fourths of the shaft of the next feather also buffy white ; under tail-coverts buff, with a brown mark in the centre near the tip. The figures are of the natural size. The plant is the Erythrochiton Brasiliense.