THE oral administration of acetylsalicylic acid or the intra-muscular injections of sodium salicylate were found by me1 to have no influence on the pituitary-adrenal axis of chickens. High levels of acetylsalicylic acid (0.58 per cent) depressed body-weight while low levels (0.07 and 0.15 per cent) did not influence body-weight or pro-thrombin time. A later report by Hutchins et al.2 confirmed that sodium salicylate did not influence the pituitary-adrenal axis in chickens. These workers also reported that immature chicks acclimatized to 105° F and fed sodium salicylate had lower body-temperatures than controls not fed sodium salicylate. The purpose of this investigation was to determine the influence of acetylsalicylic acid on the body-temperature of heat-stressed birds.