The section is arranged broadly chronologically, with the exception of a batch of files at the end of the sequence (GCPP Megaw 4/8-11) which comprises papers relating to work refereed by Helen Megaw on behalf of others. See also GCPP Megaw 3/25 for papers relating to conferences on felspars: these have been kept together with Helen Megaw's research notes and correspondence on felspars in order to retain intact her own arrangement of her main series of papers on felspars.