. Animal locomotion, or Walking, swimming, and flying, with a dissertation on aëronautics. Animal locomotion; Aeronautics. 76 ANIMAL LOCOMOTION. In the Sea-Bear (Otaria juhata) the anterior extremities attain sufficient magnitude and power to enable the animal to progress by their aid alone; the feet and the lower portions of the body being moved only sufficiently to maintain, correct, or alter the course pursued (fig. 73). The anterior extremities are flattened out, and greatly resemble wings, particularly those of the penguin and auk, which are rudimentary in character. Thus they have a thic
. Animal locomotion, or Walking, swimming, and flying, with a dissertation on aëronautics. Animal locomotion; Aeronautics. 76 ANIMAL LOCOMOTION. In the Sea-Bear (Otaria juhata) the anterior extremities attain sufficient magnitude and power to enable the animal to progress by their aid alone; the feet and the lower portions of the body being moved only sufficiently to maintain, correct, or alter the course pursued (fig. 73). The anterior extremities are flattened out, and greatly resemble wings, particularly those of the penguin and auk, which are rudimentary in character. Thus they have a thick and comparatively stiff anterior margin; and a thin, flexible, and more or less elastic posterior margin. They are screw structures, and when elevated and depressed in the water, twist and untwist, screw-fashion, precisely as wings do, or the tails of the fish, whale, dugong, and Fig. 37.—The Sea-Bear {Otaria juhata), adapted principally for swimming and diving. It also walks with tolerable facility. Its extremities are larger than those of the seal, and its movements, both in and out of the water, more xaried.—Original. This remarkable creature, which I have repeatedly watched at the Zoological Gardens^ (London), appears to fly in the water, the universal joints by which the arms are attached to the shoulders enabling it, by partially rotating and twisting 1 The unusual opportunities afforded by this unrivalled collection have enabled me to determine with considerable accuracy the movements of the various land-animals, as well as the motions of the wings and feet of birds, both in and out of the water. I have also studied under the most favour- able circumstances the movements of the otter, sea-bear, seal, walrus, porpoise, turtle, triton, crocodile, frog, lepidosiren, proteus, axolotl, and the several orders of Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and a
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectaeronau, bookyear1874
