It is in this matter that the famous archaeopteryx plays an important part.
The birds we described (after the archaeopteryx) also belong to the Cretaceous, and they form another of the doomed races.
The importance of archaeopteryx justifies the following descriptive detail.
The only form referred to this subclass of extinct birds is archaeopteryx, the earliest known bird.
Of great interest are the remains of the earliest known bird (archaeopteryx) from the Solenhofen slates of Bavaria.
In archaeopteryx however but five vertebrae take part in the formation of the sacrum.
Nor do I think it likely that the transition from the reptile to the bird has been effected by such a form as archaeopteryx.
In the wing of nearly all birds the ulna is thicker than the radius, but in archaeopteryx the two bones are equal in size.
It seems just possible that in archaeopteryx the metapatagium was more Bat-like.
The Ratitae differ from archaeopteryx and the great majority of Carinatae in being flightless.
An extinct primitive bird of the genus Archaeopteryx of the Jurassic Period, having characteristics of both birds and dinosaurs. Like dinosaurs, it had a long, bony tail, claws at the end of its fingers, and teeth. Like birds it had wings and feathers. Many scientists regard it as evidence that birds evolved from small carnivorous dinosaurs. See Note at bird.