Specimens of Archaeopteryx feather's earlier discovery, von Meyer made the London fossil the type specimen of the genus ("Archaeopteryx") and species ("lithographica"), establishing it as the exemplar of the species' features. Its discovery and subsequent descriptions, a mere handful of years after Darwin's "On the Origin of Species", fulfilled the hope of a truly transitional form in its then-unique amalgamation of bird and reptilian characters. The specimen is preserved on two counter slabs broken originally into four pieces. The main, overlaying slab contains most of the skeletal elements, while only impressions and a few bone fragments are visible on the counter slab. This
Specimens of Archaeopteryx its aerodynamic function as a flight feather. As the feather bears little resemblance to the retrices of the other full "Archaeopteryx" skeletons, it is generally thought to be a wing feather: Griffiths and others have concluded it was a remex, while Carney in 2012 interpreted it to be a covert feather. The feather has a relatively low degree of asymmetry, which Speakman and Thompson in 1994 concluded to indicate it as a secondary remex. If this is the case, then it would have originated from an animal smaller than even the Eichstätt specimen, which is the smallest "Archaeopteryx" specimen known