. A manual of zoology. Zoology. 536 CHORDATA In the hind liml)s occur conditions sinailar to tliose in the ungulates. The weight of tlie body makes it necessary that the simplification found in the wing should be repeated in the lower leg and foot, and that the numerous bones usually occurring in these regions be replaced by one r? «'. Fig. 587.—A, leg of Buleo vulgaris, a, femur; h, tibio-tarsus; b'. remains of fibula; c, tarso-metatarsus, c', same, front view; d-d', toes. B, lower leg of bird embryo; C, of /, femur; t, tibia; />, fibula; Is. tarsales of first row (talus'); //, ta
. A manual of zoology. Zoology. 536 CHORDATA In the hind liml)s occur conditions sinailar to tliose in the ungulates. The weight of tlie body makes it necessary that the simplification found in the wing should be repeated in the lower leg and foot, and that the numerous bones usually occurring in these regions be replaced by one r? «'. Fig. 587.—A, leg of Buleo vulgaris, a, femur; h, tibio-tarsus; b'. remains of fibula; c, tarso-metatarsus, c', same, front view; d-d', toes. B, lower leg of bird embryo; C, of /, femur; t, tibia; />, fibula; Is. tarsales of first row (talus'); //, tarsalcs of second row; between these intertarsal joint; /-!', digits [tiom Gcgcnbaur). to support the pressure (fig. 5S7). Therefore the filntla, well developed in the embryo [B), becomes reduced to an inconspicuous rudiment; the metatarsals, distinct in the embryo (B), fuse to a single tarso-metatarsus (^4, c), which has below as many articular surfaces as diere are toes (since the fifth toe only appears in the embryo, at most four, in some three or even two, d-d'"). At the same time the tarsals disappear by fusion with adjacent parts. ]*]ven in reptiles (C) a part of the tarsals unite witli the bones of the shank, and the remainder with the metatarsals; in the birds the union is completed, the proximal series fusing with the lower end of the tibia to form a tibio-tarsus, the distal with the metacarpus to form the tarso-metatarsus, in this way producing the intertarsal joint so characteristic of Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hertwig, Richard, 1850-1937; Kingsley, J. S. (John Sterling), 1854-1929, ed. and tr. New York, H. Holt
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1912
