Specimens of Archaeopteryx resembling a flying squirrel. After conducting an embryological comparison with modern birds, he noticed a similarity between "Archaeopteryx" and the embryonic stage of birds, concluding that the former was likely an "archetype", or created kind, of the bird lineage. Owen's monograph presented a description of the osteology and the plumage, though he missed a number of elements. Owing to its overall similarity to the structure of modern birds, Owen postulated a toothless, horny beak-like instrument "fitted for preening", and misinterpreted the fragment of an upper jaw with teeth, located next to the pelvis on the specimen, as the remains of
Specimens of Archaeopteryx under his control and full exposed, his subsequent study and monograph was the first comprehensive description of an "Archaeopteryx" specimen that had not been disarticulated. The Berlin specimen of "Archaeopteryx" is to date the most complete existing specimen of this genus, and is widely regarded as one of the most beautiful fossils in the world. Its well-preserved skeleton and the preserved feathers of its wings and tail have made it of considerable interest to a wide range of scientific study, beginning with Wilhelm Dames and Carl Vogt shortly following its discovery. This iconic fossil preserves the animal with an articulated