. Annals of the Lyceum of Natural History of New-York. Science. 150 On the Tarsus and Carpus of It surely is not the distal end of the fibula, for in the larger specimen of tibia examined (fig. 4) I find, with the aid of a hand lens, a delicate tendinous thread running from the lower end^ of the fibula and the upper end of the pre- tibial bone, and passing each other, showing no sign of ap- proximation. Furthermore, in all the embryo birds I have thus far examined (see plate iv), the fibula shows no signs of torsion. Dismissing the idea that it represents a third bone of the leg, "
. Annals of the Lyceum of Natural History of New-York. Science. 150 On the Tarsus and Carpus of It surely is not the distal end of the fibula, for in the larger specimen of tibia examined (fig. 4) I find, with the aid of a hand lens, a delicate tendinous thread running from the lower end^ of the fibula and the upper end of the pre- tibial bone, and passing each other, showing no sign of ap- proximation. Furthermore, in all the embryo birds I have thus far examined (see plate iv), the fibula shows no signs of torsion. Dismissing the idea that it represents a third bone of the leg, "as contrary to all analogy," we have only to admit that it represents a new tarsal bone of the proximal series. The specimen represented in figure 1, was sent to me by Prof. WN'man sometime before he had examined the other bones with reference to this new tarsal. In this specimen the meta- tarsals are still separate, and the presence of the three tarsal bones thus far described is but dimly made out; yet the pretibial bone is quite distinct, and of much importance is the fact that its lower edge is below the lower edge of the tibia. Satisfied that it is a true tarsal bone, to what bone in the tarsus shall we compare it? After studying over it very carefully, and comparing it with figures of certain amphibians, given by Gegenbaur, and with some of my own drawings of the tarsus of the com- mon wood salamander, , I believe it to represent the intermedium of Gegenbaur. In the tarsus of Salamandra maculosa, as given by Gegenbaur, the inter- medium is represented as a much elongated bone, broader at the bottom, and wedged between the tibia and fibula, half of it being actually above the distal margins of these two bones. Above the reptiies, the intermedium is supposed by Gegenbaur to coalesce with the tibiale or astragalus. In other words the astragalus represents the intermedium and tibiale, connate. Gegenbaur believes that the astraga- lus represents the
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