HYPUROPTILA MELANORRHOA, Gouwid. Black-vented Plumeleteer. Chalybura melanorrhoa, Salvin, P.Z.S8. 1864, p. 585.—Scl. & Salv. Nomencl. Av. Neotr. p. 82.—Elliot, Synopsis Trochil. p. 47. Chalybura carmioli, Lawr. Proc. Acad. Nat. Sci. Philad. 1865, p. 39. Lampornis melanorrhoa, Mulsant, Hist. Nat. Oiseaux-Mouches, vol. i. p. 174. Polytmus melanorrhous, Gray, Hand-l. B. vol. i. p. 126. Tue first discoverer of this species was the well-known collector Enrique Arcé, who procured it at Tucurrique in Costa Rica; and shortly after, Mr. Lawrence found specimens in the Smithsonian Institution, collected by Mr. Carmiol at Angostura, in Costa Rica, which he described as Chalybura carmioh. Though nearly allied to C. isaure, it is easily distinguished by the black vent, which is white in the first- named bird; and there can be no doubt that the two species are quite distinct. Mr. Salvin remarks that his C. melanorrhoa, with C. tsaure, forms a somewhat abnormal section of the genus; “but the differences, as seen from our present materials, are hardly of sufficient importance to warrant a generic separation. They may be briefly stated as follows:—The plumage in the Chalybura is generally more brilliant; the uropygium is nearly the same colour as the back ; in the Costa-Rica bird it is clearly defined. The plumed feathers of the crissum, in the former, are much more developed.” This species, as at present known, is only found in Central America, where it occurs in Costa Rica and Veragua. The diagnosis given by Mr. Elliot for this species is as follows :— Male. Head and upper parts dark grass-green ; rump purplish bronze ; wings purplish brown; under- parts very dark shining grass-green ; abdomen dark brown glossed with green; under tail-coverts black ; tail dark bronzy purple ; maxilla black ; mandible flesh-colour. Total length 42 inches, wing 28, tail 15, culmen %.” The principal figures in the Plate represent two males, of the size of life.