. The bird, its form and function . FiG. 88.—Lower iTianclil)le, tongue, and hyoid bones of Bald Eagle. arch forms the bones of the upper jaw, palate, jugal, andquadrate, and the lower jaw completes the entire central part of the second gill fades into nothing,but the top is present as the columella-bone of the ear,while the base is transformed into the head and twoblunt barbs of the arrow-like bone of the tongue. Thetwo long barbs of this bone correspond to the third gill The Skull 115 and, from their rod-Uke jointed charncler, tlicv lookvery much like the real gill-arches of a lisli
. The bird, its form and function . FiG. 88.—Lower iTianclil)le, tongue, and hyoid bones of Bald Eagle. arch forms the bones of the upper jaw, palate, jugal, andquadrate, and the lower jaw completes the entire central part of the second gill fades into nothing,but the top is present as the columella-bone of the ear,while the base is transformed into the head and twoblunt barbs of the arrow-like bone of the tongue. Thetwo long barbs of this bone correspond to the third gill The Skull 115 and, from their rod-Uke jointed charncler, tlicv lookvery much like the real gill-arches of a lisli. khc fourljiarcli vanishes. Such is the almost incredil)le alchemy which Naturehas wrought from a plastic rod of gristle,—transformingit into beak, tongue, and ears. Few of us, when watcli-. FiG. 89.—Ultimate cUstrilmtion of the four pml)rvoiiic KilI-:irchos in (lie skullof the atliilt bird. The dotted [ are not dcNcloped. (.Vdapted fromNewton.) Compare with Figs. HA and SS. ing the gently waving gills of a fish, have realized howmuch we indirectly owe to them. A noted (lermananatomist—Karl Gegenl)aur—l)elieves tliat we owe Qveiiour hands and arms (by way of the pectoral fins of fishes)to portions of the gill framew^ork, but this theory is notgenerally accepted.
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Keywords: ., bookauthorbeebewil, bookcentury1900, bookdecade1900, bookyear1906
