IN June 1937 a colloquium on sex hormones was held in Paris under the auspices of La Fondation Singer-Polignac. This colloquium was attended by men of science from France, Denmark, the United States, Canada, Great Britain, etc. The meeting lasted ten days, morning and afternoon sessions being held for the reading of papers on most days. The wide international representation of active investigators led to great interest being taken in the papers and to vigorous discussion. The papers presented, together with summaries of the discussions, were afterwards published in one volume for private circulation. They have now been republished in five numbers, each containing five papers, in the series of “Actualites Scientifiques et Industrielles” (Paris: Hermann et Cie). The first number appears under the general title “lies Proprietes des Hormones Sexuelles”. The second number deals with “Ovula-tion, Menstruation, Gestation”. The third contains papers dealing with the pituitary. The fourth is entitled “Regulations generates. Influence des facteurs nerveux et externes”; and the fifth number contains papers on a variety of subjects such as pathology, toxicity, antihormones and cancer. The final publication of this material concludes the record of the colloquium, which will be long remembered by those taking part as a particularly happy and profitable occasion upon which La Fondation Singer-Polignac should be most heartily congratulated.