If de Bergerac's usage doesn't match the criteria because they are basically Earth birds, just intelligent, the next best answer I have is Camille Flammarion's 1889 work Uranie (translated to English 1890 as Urania).
The author, along with the titular Urania, have left the solar system and are visiting "Gamma Andromedæ" where they find a race that live their entire lives in the air:
But, as I have said, we were approaching one of the worlds belonging to the system of the sapphire sun. Everything was blue,—landscapes, water, plants, rocks,—slightly greenish on the side lighted by the second sun, and hardly touched by the rays of the orange sun, which was rising on the distant horizon. As we floated into the atmosphere of this world a soft, delicious music was wafted into the air like a perfume, a dream. Never had I heard anything like it. The sweet, deep, distant melody seemed to come from a choir of harps and violins, strengthened by an accompaniment of organs. It was an exquisite anthem, which charmed at once; it needed no analyzing to be understood; it filled the soul with ecstasy. It seemed to me that I could have lingered there listening for an eternity. I was so fearful of losing a single note that I dared not speak to my guide. Urania noticed it; stretching out her hand toward a lake, she pointed to a group of winged beings who were hovering over the blue waters.
They had not the earthly human form. They were beings who had evidently been created to live in air. They seemed woven out of light. At a distance I thought they were dragon-flies; they had their slender, graceful shape, the same wide wings, quickness, and lightness. But on examining them more closely I noticed their height, which was not inferior to our own, and realized from the expression of their eyes that they were not animals. Their heads were very like that of the dragon-fly, and like those aerial creatures they had no legs. The delicious music to which I had been listening was but the noise of their flight. They were very numerous,—perhaps many thousands.
From the Project Gutenberg reproduction of the 1890 translation of Urania
The book also includes a race of men who form a chrysalis on death and are reborn in a butterfly-like form, and a race from Mars ("Martials") who are basically intelligent flying plants:
Everything there is more aerial, more ethereal, and less material. The Martials might be called winged, sentient, living flowers; but in fact no earthly being can serve as comparison to aid us in imagining their form and manner of existence.
ibid