Letter from Howard Walter Florey to the Editor, the Lancet Refers to Annotation in Lancet on synnematin B - comments on his colleagues' work suggesting that cephalosporin N is the same as synnematin B and that both are a new kind of penicillin - American work confirms this - refers to summary of Oxford work in Annals of Internal Medicine and comments on this work - Dr Olson has told (E P) Abraham that several strains of S typhi are more sensitive to penicillin N than to penicillin G - this claim has to be substantiated. 16 September 1955