The correspondents are:
Professor George D Pappas (dismissal of Greek academics), Dr H Hasko Paradies, John E Parnell, A L Patterson, Dr S M Partridge, Dr Chester Partridge, Professor W D M Paton (cannabis), Professor Linus Pauling (three hydrogen bonds between guanine and cytosine), Dr A R Peacocke (British Biophysical Society talk, 1966), Dr Stephen R Pelc (model-building), Dr J W Peltason, Walter Penney, Dr Lionel Penrose (fingerprints), Dr F Persico, Dr Max Perutz, Dr Ward Pigman, Dr David Pines, 'Plastic-Union', Police College Library (fingreprints), Professor G Pontecorvo, Professor Martin R Pollock, Professor R R Porter (including a draft lecture on immunoglobulin structure, with Crick's detailed response), Professor Van R Potter, Dr D M Potts (International Planned Parenthood Federation), D Kedar N Prasad, Mrs Frederick W Pratt (Huntingtons Chorea), Dr George R Price, Professor J W S Pringle, Professor R H Pritchard, and Professor Frank W Putnam.