. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. Fig. 29.—Skeleton of the Perch Perec, fluviatilis . Shows the jointed nature ofthe vertebral column, and the facilities afforded for lateral motion, particu-larly in the tail id), dorsal (e,/), ventral ?>. c), and pectoral (a), fins, whichare principally engaged in swimming. The extent of the travelling sur-faces required for water greatly exceed those required for land. Compare thetail and fins of the present figure with the feet of the ox, fig. IS, p. 37.—(After Dallas.). Fio. 30.—The Salmon (
. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. Fig. 29.—Skeleton of the Perch Perec, fluviatilis . Shows the jointed nature ofthe vertebral column, and the facilities afforded for lateral motion, particu-larly in the tail id), dorsal (e,/), ventral ?>. c), and pectoral (a), fins, whichare principally engaged in swimming. The extent of the travelling sur-faces required for water greatly exceed those required for land. Compare thetail and fins of the present figure with the feet of the ox, fig. IS, p. 37.—(After Dallas.). Fio. 30.—The Salmon ( ) swimming leisurely. The body, it will beobserved, is bent in two curses, one occurring towards the head, the othertowards the tail. The shape of the salmon is admirably adapted for cleav-ing the water.—Or This, my readers are aware, consists of a lashing, curvi-linear^ flail-like movement of the broadly expanded tail, whichoscillates from side to side of the body, in some instances withimmense speed and power. The muscles in the fish, as has- CG ANIMAL LOCOMOTION. been explained, are for this purpose arranged along the spinalcolumn, and constitute the bulk of the animal, it being a lawthat when the extremities are wanting, as in the water-snake,or rudimentary, as in the fish, lepidosiren,1 proteus, andaxolotl, the muscles of the trunk are largely developed. Insuch cases the onus of locomotion falls chiefly, if not entirely,upon the tail and lower portion of the body. The operationof this law is well seen in the metamorphosis of the tad-pole, th
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Keywords: ., bookcentury1800, bookdecade1870, booksubje, booksubjectphysiology
