Corresponding letters. (1) Letter from H H Gunson to Professor F G J Hayhoe, University of Cambridge Clinical School, Department of Haematological Medicine, re Policy for blood donors who have visited Africa. (2) Letter from F G J Hayhoe, Department of Haematological Medicine, to Dr H H Gunson, Regional Transfusion Centre dated, re Notice of a finding prepared for publication by Dr A Karpas.