. Bulletin of the British Ornithologists' Club. Birds. J. F. R. Colebrook-Robjent & J. E. Griffith 245 1996 116(4). Figure 1. Eggs of Forbes's Plover. Zambezi Rapids, Zambia, 7 October 1990. by Johnsgard (1981), and Jehl (1968) does not mention or list forbesi in his study of the downy young of shorebirds. Snow (1978) places C. tricollaris and forbesi in a species-group, commenting on "the evolution of the two species from a single widespread common ancestor" (p. 183). Urban et al. (1986) go further and consider them to be members of a superspecies and Marchant et al.
. Bulletin of the British Ornithologists' Club. Birds. J. F. R. Colebrook-Robjent & J. E. Griffith 245 1996 116(4). Figure 1. Eggs of Forbes's Plover. Zambezi Rapids, Zambia, 7 October 1990. by Johnsgard (1981), and Jehl (1968) does not mention or list forbesi in his study of the downy young of shorebirds. Snow (1978) places C. tricollaris and forbesi in a species-group, commenting on "the evolution of the two species from a single widespread common ancestor" (p. 183). Urban et al. (1986) go further and consider them to be members of a superspecies and Marchant et al. (1986) also consider them to be close relatives. We do not agree with any of the foregoing, rather we concur with Sibley & Monroe (1990) that these two species are "different morphologically" (p. 217). We are especially impressed by the differences in the eggs, as previously pointed out by Serle (1956). However, in our opinion, the choice of the egg specimen of C. tricollaris photographed alongside the egg of forbesi in Serle's paper is unrepresentative. This egg is clearly depicted as subelliptical in shape and densely and evenly covered in scrawls, which makes it appear more like Cursorius africanus than a typical egg of C. tricollaris. One of us () has examined 64 eggs of C. tricollaris in Zambia and none have been subelliptical, but all were pyriform or pointed oval. The eggs of tricollaris are indeed well marked with fine scrawls or hair lines of black or dark brown, but seldom evenly spread over the surface and most often concentrated in one, two or three heavy bands around the egg. The ground varies from cream to pale ivory-yellow. The egg specimen of forbesi in Serle's plate is a good example and is much like our own from Zambia, though ours are shorter and more rounded. The best and fullest description of the eggs of tricollaris is by James (1922), based on the study of 200 nests which he had found in South Africa. By. Please note that these images
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