Several naturalists and admirers of ornithology have formed special collections of Humming Birds, and there are now extant several which contain very nearly all the known species, of which may be mentioned those of Mr. Edward Wilson, and Mr. John Gould, in England, and of Messrs. Edward and Jules Verreaux, in Paris. That of the first named, who is an American gentleman resident in England, is the most extensive and complete, and includes several of the only specimens known of the species which they represent. This gentleman and his brother, Dr. Thomas B. Wilson, of Philadelphia, have won for themselves the imperishable respect and gratitude of American naturalists, by forming in their native city the most extensive library and collections in natural history in America, and, in some departments, unrivalled by any in the old world. For these, now constituting, mainly, the magnificent museum and library of the Academy of Natural Sciences of Philadelphia, it is indebted to the distinguished patrons of zoological science whom we have just mentioned. EMBERIZA BILINEATA.—Cassin. The Black-throated Finch. PLATE XXIII.—Adult Male. This curious little Finch was discovered in Texas, in 1849, by Mr. John W. Audubon, a son of the celebrated ornithologist, and himself a naturalist and zoological draughtsman of high merit and accomplishments. It appears to be extensively diffused throughout Mexico, Texas, and New Mexico, and in the former country is a common species. In the States last mentioned, it has been noticed by nearly all the naturalists who have visited them; though, as a bird of the United States, little beyond the fact of its existence in those regions has been placed on record, or has otherwise come to our knowledge. In Mexico, this bird was found by Lieut. Couch to be numerous in some parts of Tamaulipas, Nueva Leon, Coahuila, and other States on the Rio Grande, immediately south and west of the limits of the territory of the United States. For our present article, this gentleman has very kindly furnished the following interesting communication, for which and other similar favors we beg to tender our grateful acknowledgments:— “This bird was first seen at Santa Rosalio, and specimens were obtained. Though a month had been spent at Brownsville, in Texas, only about twenty miles distant, it had not been observed. At Charco Escondido, forty miles farther in the interior, it was very plentiful, and early in March, seemed to have already reared a breed of young; one specimen procured, having the appearance of being a young bird but a few weeks old.