. Bulletin of the British Ornithologists' Club. 1959 139 Vol. 79 running from the upper mandible to the eye. In the eclipse drake, it is most easily seen in that type which develops a dark smokey coloured head and neck, except for the crescent, which is pale straw-coloured, spotted with sepia. This is the type we have illustrated. Anas rhynchotis, the Australasian Shoveler, is closely related to the Northern Shoveler, as evidenced particularly by display and behaviour and it also shows a remarkable similarity in head pattern and colour to the Blue-winged Teal, so that the presence of the pale
. Bulletin of the British Ornithologists' Club. 1959 139 Vol. 79 running from the upper mandible to the eye. In the eclipse drake, it is most easily seen in that type which develops a dark smokey coloured head and neck, except for the crescent, which is pale straw-coloured, spotted with sepia. This is the type we have illustrated. Anas rhynchotis, the Australasian Shoveler, is closely related to the Northern Shoveler, as evidenced particularly by display and behaviour and it also shows a remarkable similarity in head pattern and colour to the Blue-winged Teal, so that the presence of the pale facial crescent in North- ern Shoveler is further evidence of the affinities of these species. It has however, a still greater significance when consideied in conjunction with. No. 4. Eclipse drake, ,1944, showing pale crescent of face. bridling and bimaculation of the face. This has already been described in certain hybrids, notably a Teal X Shoveler2, Wigeon X Shoveler4, Pintail X Teal17 and the so-called "Bimaculated Duck"18—a Mallard X Teal. In all of these, the cheeks are pale-coloured and are sharply divided by a vertical line running downwards and slightly backwards below the eye, to give the appearance strongly suggestive of the drake Baikal Teal, Anas formosa Georgi. Such hybrids provide evidence that these remarkable facial patterns are ancestral in character, arising by gene recombination as the result of hybridisation, although we have recorded bridling, in which the cheeks are divided into two by a similar line of different colour in the European Green-winged Teal, Anas crecca crecca Linnaeus, and in duck Baikal Teal variants. We now think that the pale facial crescent of the Australasian Shovelers and the Northern Shoveler is homologous with the anterior. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly r
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