. Bulletin of the British Ornithologists' Club. Birds. A B Figure 1. Proximal view of right tarsometatarsi in two species of toucans (Ramphastinae) to show individual variation in ossification of the small septum (arrows) dividing the hypo- tarsal loop enclosing the flexor tendons: A, Andigena nigrirostris USNM 428774; B, A. hypoglauca USNM 428789. The presence or absence of this septum determines whether there are one or two hypotarsal canals, but changes neither the number nor placement of the flexor tendons. We are not talking here about the development of some significant evolutionary nove
. Bulletin of the British Ornithologists' Club. Birds. A B Figure 1. Proximal view of right tarsometatarsi in two species of toucans (Ramphastinae) to show individual variation in ossification of the small septum (arrows) dividing the hypo- tarsal loop enclosing the flexor tendons: A, Andigena nigrirostris USNM 428774; B, A. hypoglauca USNM 428789. The presence or absence of this septum determines whether there are one or two hypotarsal canals, but changes neither the number nor placement of the flexor tendons. We are not talking here about the development of some significant evolutionary novelty. The change from a single to a double hypotarsal canal does not involve the addition of a new canal or the displacement of flexor tendons, but nothing more than the ossification of a septum between two already discrete portions of the original single canal (Fig. 1). Perhaps all members of the Pici progress from the single to the double condition during their ontogeny by such ossification, which in turn may have taken place several times during the phylogeny of the Pici. Very little searching among modern skeletons was needed to find an example within the Pici (an individual of the toucan Andigena hypoglauca) in which this ossified septum was lacking, leaving it with a single hypotarsal canal (Fig. 1). This character probably has little or no phylogenetic significance. If it really is present in Capitonidesprotractus, which, after all, is more than 15 million years old, why should this not simply be regarded as a minor primitive condition? If so, it would certainly not provide a basis for the creation of a new family. Capitonides protractus appears to be referable to the modern genus Trachyphonus, and the type species, C. europaeus, may be as well. I reject the name Capitonididae Prum, 1988, as a junior synonym of Ramphastidae Vigors, 1825, in the newly expanded sense, and as a junior synonym of Capitonidae Bonaparte, 1846, in the traditional sense. Because Capitonides and T
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