English: Gerhard Heilmann's comparative illustrations, redrawn from William Beebe's illustrations, of the hindlimbs of various immature birds and one reptile: four-day old squab of white-winged dove (1), detail of same showing pelvic wing (2), squabs of domestic pigeon, four days old (3) and a few days older (4), pheasant nestling (5), squab of shag (6), green woodpecker hind-limb (7), and fringed gecko (8).
Датум
Извор
The Danish book Vor Nuvaerende Viden om Fuglenes Afstamming
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|Description = Gerhard Heilmann's comparative illustrations of the hindlimbs of various immature birds and one reptile: four-day old squab of white-winged dove (1), detail of same showing pelvic wing (2), squabs of domestic pigeon, four