The sharp northwest wind continued late, and the night became clear and cold. Shortly after midnight the bright moon showed the temperature, by a thermometer which I had hung beside the camp, to be 35°, and at sunrise it stood at 32°. Before daylight I was standing on a boulder of conglomerate on the dim mountain’s brow listening for the awakening of the birds. The first songs heard were those of the Hermit Thrush, Snowbird, and Yellow-bellied Flycatcher, which began almost simultaneously, followed a little later by those of the Olive-backed Thrush and the Mourning Warbler, but H. bicknelli was not heard, or at least not near enough to be distinguished among the other species.
The increasing light upon the mountain seemed to attract the birds from below, whither, perhaps, they had retired for the night, and soon many different notes were to be heard about the camp; not, however, in that boisterous chorus with which the day is often announced about our homes, in which the notes of many individuals of many species are blended in such confused medley that separate voices are almost indistinguishable, but simply the association of a few vocalists, the very isolation of whose position endowed their voices with an additional interest and charm.
After those already mentioned the Black-poll Warbler (Dendrœca striata) began its unpretending notes, which always to me suggest a short dotted line, and this song, with that of the Black-and-Yellow Warbler, occasionally alternated about us in agreeable contrast. Now and then a Canada Nuthatch, on its morning tour, tarried to inspect some dead trunk or thinly clothed tree, upon the projecting apex of which, or that of some companion, a solitary Purple Finch occasionally alighted, and with a few wild fugitive notes was gone, to other mountain tops or the forests of the descending slopes.
But to revert to the Thrushes. The two specimens of the new form which were obtained were both males, and were unquestionably breeding,[[76]] though no nest known to belong to their species was found.
It remains to briefly consider some facts furnished by the birds’ occurrence as narrated. These facts bear directly on the long contested question of the relationship which H. aliciæ and H. swainsoni bear to one another, and it can scarcely be denied that the present evidence on this point is conclusive. Not only have we representatives of both birds preserving their respective identities at the same locality, under identical conditions of environment, but examples of each taken under these circumstances, display, except in size, even a greater dissimilitude than those which occur together on their migrations. There is but one tenable interpretation of these facts: the birds—Hylocichla aliciæ and H. ustulata swainsoni—are wholly and entirely distinct. Any theory of dichromatism which might be advanced, aside from its extreme unlikelihood, would be shown inadequate by the relative differences in proportions of parts which the two birds exhibit. These differences, as well as those of color are illustrated by the Catskill birds. A specimen of H. swainsoni taken at the top of Slide Mountain was in every way typical of its species, and conspicuously unlike the examples of bicknelli taken at the same time. Aside from differences in the proportions of parts, the two birds were strikingly different in color, the decided grayish olive tinge of the superior surface of swainsoni contrasting strongly with the much darker brownish cast of its congener. One example of the latter instead of showing indications of a buffy tinge about the sides of the head and on the breast, which under the circumstances we should expect to be the case, were it in any way specifically related to swainsoni, has absolutely no indications whatever of this shade about the sides of the head, and actually less on the breast than any specimens of true aliciæ that I have seen, and this little most evident low down where the corresponding shade in swainsoni begins to pale. It seems probable that this newly recognized race of aliciæ is responsible for much of the ambiguity which the discussion of both species by different writers has occasioned. Indeed, it seems to occupy the same position relative to aliciæ proper which, by some, swainsoni was supposed to hold, viz., the more southern-born individuals of the species, but that it represents a link specifically connecting the two, the facts already presented refute. As it occurs with true aliciæ on the autumn migration most specimens of the new form are paler and more brownish in color above, and their general size is nearly that of swainsoni,[[77]] and these differences may be regarded by some as approaches towards the latter species. In both species there is a wide individual variation, but the closest approach of each towards the other never exceeds that limit within which each may vary without its specific distinctness being compromised. I have yet to see a specimen of either which would admit of the slightest question as to its identity. I speak thus of adult birds. In such closely related species the young must almost necessarily approximate, and to these we must appeal for light on the things that have been—on the question of origin—whether one has been derived from the other, or both species from a common ancestor. Such obscure insight into this point as I have been permitted seems to indicate that the latter alternative will be found to be the more correct, but, for the present, from lack of the necessary data this important subject is proscribed.
It is unnecessary here to repeat the diagnosis of the new form of Hylocichla aliciæ given by Mr. Ridgway in the paper before cited. As this writer states, the race breeds “probably in other mountainous districts of the northeastern United States” than the single locality where it was discovered, and it seems very singular that up to the present time we have no knowledge of its occurrence in the summer season elsewhere, even in regions where the two congeneric species with which it was here associating—H. nanus[[78]] and H. swainsoni—are well known to be common summer residents. The occurrence of a representative of H. aliciæ in the United States at all during its breeding season is a matter of surprise, especially when we recollect the boreal distribution of the typical form during that period, and read[[79]] that so far towards the north as the Yukon and the Great Slave Lake it occurs “only as a bird of passage to and from more northern breeding grounds.” Additional information respecting the distribution of the new race will be awaited with great interest.
SHORT NOTES ON THE BIRDS OF BAYOU SARA, LOUISIANA.
BY CHARLES WICKLIFFE BECKHAM.
As the avian fauna of the lower Mississippi Valley is now receiving some attention,[[80]] it seems well that I should contribute my mite of information to the general fund.
Bayou Sara and the adjoining town of St. Francisville, in the parish of West Feliciana, are situated on the east bank of the Mississippi River, 170 miles above New Orleans by that stream and about 80 miles in an air line northwest of it. It is 30 or 40 miles north of Baton Rouge, near which place Dr. Langdon made his observations in April, 1881. The following notes were made principally on and near “Wyoming,” two miles from the river, the plantation of Ex-Gov. R. C. Wickliffe, a place possessing peculiarly agreeable ornithological associations on account of its former owner, Gen. Dawson, having entertained Audubon as his guest for several months. It will be remembered that the type specimen of Buteo harlani was captured here.