Letters Regarding "The Evolution of Flying and Flightless Birds" Letters received by De Beer from P B Medawar; the Clarendon Press, Oxford; the British Museum; A J Charig; and Dr J J Head: commenting on his draft The Evolution of Flying and Flightless Birds; discussing De Beer's previous work on the Archaeopteryx and other flightless birds; regarding drawings of Archaeopteryx and Ratites; and regarding payment and publication arrangements. Enclosed with the letters are a photocopy of "Archaeopteryx: Notice of a "New" Specimen", Science, 170, (1970), pp. 537-538; photographs of Archaeopteryx fossils; and a copy agreement. 1972