In previous articles on the subject of the effect of roentgen rays on glandular activity, we have presented evidence showing that the submixillary and gastric glands are not stimulated by small doses of roentgen rays, but that their secretion can be depressed with relatively large doses.1German authors have for years been quoting what they call the Arndt-Schulz law, which states that small doses of an active agent stimulate, moderate doses depress or paralyze, and large doses destroy or kill, and have been assuming and claiming that this law applies to the action of the roentgen rays. On the basis of biologic principles and facts we could not accept this law, at least as applying to the action of roentgen rays on glandular activity2and our view has been supported by our experimental observations up to date. Our results on this point have also been corroborated recently by