Protoavis are well preserved, and they are astonishingly non-avian. The distal carpals, while long, are in no way similar to those observed in the urvogel or other archaic birds. There is no semilunate element, and the structure of the radiale and ulnare would have limited the flexibility of the wrist joint. The manus is not tridactyl, and metacarpal V is present. In even the most basal avialian, "Archaeopteryx", there is no vestige of the fifth metacarpal and its presence in "Protoavis" seems incongruous with the claim that it is a bird, let alone one more derived than "Archaeopteryx". Chatterjee claims that
Specimens of Archaeopteryx ähnlichen Federn bedeckten "" ("skeleton of an animal covered in similar feathers"). In German, this ambiguity is resolved by the term "Schwinge" which does not necessarily mean a wing used for flying. "Urschwinge" was the favored translation of "Archaeopteryx" among German scholars in the late 19th century. In English, "ancient pinion" offers a rough approximation. Hermann von Meyer learned of the discovery of what would later be known as the London Specimen before he published his analysis of the single "Archaeopteryx" feather. In September 1861 he wrote to the "Neues Jahrbuch" about being informed of the discovery by Friedrich Ernst