OCR Text |
Show 450 MR. J. E. HARTING ON THE [June 16, which I have seen from the above-named eastern localities seem to justify the observation that it is never larger. Now the bird from Chili, which is found also in Patagonia, and, I believe, in the Falkland Islands, is always considerably larger than V. cristatus and a fortiori than V. cayennensis. Size, however, is not the only respect in which it differs from the last-named. It will be seen on comparison that the black colour of the forehead extends further back, and encroaches more upon the cheeks ; the same colour upon the chin (which in V. cayennensis is restricted to a small patch between the rami of the lower mandible, very faintly edged with white, and passing into a mere streak which almost disappears before it reaches the black of the breast) has in the western bird the appearance of one broad patch of equal width, extending from the base and beyond the rami of the under mandible quite down to the black of the breast, into which it merges. This broad patch is very conspicuously edged with a white line, which extends from the black breast-plate upwards in front of the eye and over the crown, and so downwards on the other side, separating conspicuously the black forehead and throat from the grey of the crown, nape, and sides of the neck. The crown, nape, and sides of the head and neck in F. cayennensis are brown (or, perhaps, it would be more correct to say greyish brown), instead of pearl-grey as in the other ; and, to judge by the specimens which I have examined, F. cayennensis always has a well-developed occipital crest of black feathers, while in the other the crest is not only more scanty in appearance, but the few feathers of which it is composed are grey rather than black. In this respect it approaches Fanellus resplendens, Tschudi (F. ptilosceles, Gray), from the Peruvian Andes, which is not crested. It may be suggested that the crest is only an adornment during the breeding-season, like the frill of Machetes pugnax; but if so, this is contrary to what occurs in the case of Fanellus cristatus, and, moreover, most of the specimens forwarded from Chili were procured at a time when the birds must have had eggs or young. In addition to this, the tibia is feathered much lower down than in F. cayennensis, the tarsus is proportionally shorter and more robust, the toes proportionally shorter and less attenuated. On account of these and other less-marked differences, it appears to me that the western may be readily separated from the eastern form; and I propose to distinguish it accordingly as Fanellus Occident alis. The synonymy, habitat*, and diagnosis of the two species stand as follows :- VANELLUS CAYENNENSIS (Gmelin). Parra cayennensis, Gmelin, Syst. Nat. i. p. 706 (1788). Tringa cayennensis, Latham, Ind. Orn. ii. p. 727 (1790); id. Gen. Hist. ix. p. 300(1824). * For the present, the habitat given in each case must be considered to be only provisional, until the geographical distribution of the two becomes better known. |