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 Gallina;, 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 Passeies, 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. 



Plerocles arenarius, now (1835) 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 Grallinae. In the stuffed specimens 

 of Pterocles alchata in tiie 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 



