| OCR Text |
Show 1886.] CUBITAL COVERTS OF BIRDS. 195 the posterior, 2nd, and 3rd rows of median coverts in the distal area, which is nearly always seen in the Gallinae, the corresponding features of the Pigeon show a different and much more complex arrangement. In all the birds previously passed under notice (except the Birds of Paradise amongst the Passeres, and the Macro-chires) the feathers of both the middle and the distal area of the median coverts maintain a proximal imbrication from near the carpus backwards, various distances according to the zoological position of the bird under notice. In all the remaining birds, inclusive of the Columbae, the distal area of the median coverts is composed of feathers arranged in the opposite direction. It is somewhat difficult to reduce the facts to anything like an intelligible description; but a study of the figures may help to make the mode of arrangement clear. It will be seen by this that several feathers on the distal area of each row overlap from behind forwards, or from the proximal towards the distal margin of the wing. The feature referred to can be easily studied in the case of Domestic Pigeons ; although the general Columbine pattern can, perhaps, best be studied in the case of such conspicuously-marked exotic Pigeons as Columba guinea, Peristera geoffroii, Leucosarcia picata, and others commonly living in the Western Aviary. Pterocles arenarius, now (1885) living in the Western Aviary, shows an arrangement of the wing-feathers somewhat like that of the Pigeons, especially so far as the proximal and the distal areas of Fig. 18. the cubital region are concerned. But the distal imbrication of all the feathers next the manual region is, in the Pterocletes, carried to excess. In this respect the Pterocletes stand as far removed from .the Pigeons as these are from the Gallinae. In the stuffed specimens of Pterocles alchata in the National Collection this feature is remarkably well displayed (see fig. 18). Another point to be noticed in these birds is that the posterior row of median coverts show distal overlap throughout their entire length-an arrangement of |
