. Bird-life . ructure Avhich represents a second row of bonesat one time quite distinct. The joint, or seat ofmovement between the foot and the leg, lay be-tween these two rows of fused now to the bones of the young fowls footand leg and ankle-joint, and a precisely similararrangement will be seen. The fowl, however,goes a step further. The three long bones of thefoot, permanently distinct in the dinosaur, be-come completely merged together in the adultfowl to form but a single shaft. An ankle-jointsuch as that just described occurs in some otherreptiles, and in all birds. The
. Bird-life . ructure Avhich represents a second row of bonesat one time quite distinct. The joint, or seat ofmovement between the foot and the leg, lay be-tween these two rows of fused now to the bones of the young fowls footand leg and ankle-joint, and a precisely similararrangement will be seen. The fowl, however,goes a step further. The three long bones of thefoot, permanently distinct in the dinosaur, be-come completely merged together in the adultfowl to form but a single shaft. An ankle-jointsuch as that just described occurs in some otherreptiles, and in all birds. These are the principal points of resemblancebetween the two, but they are points of verygreat significance. The fore-limb, someone will exclaim, is verydifferent in this old reptile and the bird. Quiteso. Like the shoulder-girdle, it has in the birdundergone considerable modification and trans-formation to fit it for the purposes of fore-limb of the dinosaur has required no 232 THE STORY OF Dinosaur Fm. 7. andTo^f hSff T^ :i «^^^^^kle-joint of a dinosaur,ana ±) ot a bird to show their ^T 1 ^ metatarsal bones of a dinosaur, and D of abird to show the close resemblance E -The shoulder-girdle of a dinosaur and F of a bird :Or the hip-girdle of a dinosaur, and H of a bird. Note b^YiXomi^irsar^^^^^ ^^^^^^ ^^°^^^°^«- PEDIGREES—THE FOUNDERS OF THE HOUSE. 233 such alterations, and retains something like theoriginal five-fingered form from which it started. The bird then we have agreed is of reptilianorigin, and of the reptiles resembles most nearlythe dinosauria. Most nearly—this implies thatit has also characters wherein it resembles otherreptiles; and so it has. Of these we will nowselect a few examples. Let us take the skull. In this, in manyreptiles, we find true teeth. These are eitherimplanted in the jaws in grooves or in the earliest birds—Archceopteryx, HesperorniSyand Ichthyornis—we have also teeth in the wou
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Keywords: ., bookcentury1800, bookdecade1890, bookidbirdlife, booksubjectbirds
