Archive image from page 374 of The descent of man . The descent of man : and selection in relation to sex descentofmanseledarw Year: 1874 LAW OF BATTLE. 561 however, tke wing-spurs must be considered as a sexual character. Thus in the male of our common peewit (Vanellus cristatus) the tubercle on the shoulder of the wing becomes more prominent during the breeding-season, and the males fight together. In some species of Lobivanellus a similar tubercle becomes developed during the breeding-season 'into a short horny spur.' In the Australian L. lobatus both sexes Fig-. 38. Palamedea cornuta (
Archive image from page 374 of The descent of man . The descent of man : and selection in relation to sex descentofmanseledarw Year: 1874 LAW OF BATTLE. 561 however, tke wing-spurs must be considered as a sexual character. Thus in the male of our common peewit (Vanellus cristatus) the tubercle on the shoulder of the wing becomes more prominent during the breeding-season, and the males fight together. In some species of Lobivanellus a similar tubercle becomes developed during the breeding-season 'into a short horny spur.' In the Australian L. lobatus both sexes Fig-. 38. Palamedea cornuta (from Brehm), showing- the double wing- spurs, and the filament on the head. have spurs, but these are much larger in the males than in the females. In an allied bird, the Hoplopterus armatus, the spurs do not increase in size during the breeding-season; but these birds have been seen in Egypt to fight together, in the same manner as our peewits, by turning suddenly in the air and striking side- medea, Brehm's 'Thierleben,' B. iv. s. 740. See, also, en this bird Azara, 'Voyag-es dans FAmerique merid.' torn. iv. 1809, pp. 179, 253.
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