IN an earlier issue (Nature, 152, 619; 1943), some account of patulin was given, and the results of a clinical trial of it for the treatment of the common cold, conducted by Surgeon Commander W. A. Hopkins, R.N., with the aid of Naval personnel, as described in The Lancet (ii, 625, Nov. 20, 1943), were outlined. In that trial 57 per cent of the patients recovered completely in 48 hours, while only 9·4 per cent of the controls recovered in this time. Commander Hopkins was, however, wisely cautious about the interpretation of these results and pointed out that the etiology of the common cold is not yet fully understood. Prof. H. JRaistrick stated at the time that patulin would not be issued for general use until the results of large-scale trials had been obtained. The Lancet now publishes the results of two such trials, which fully justify the earlier caution about the effect of patulin on the common cold.