i. 1206 ABSTRACTS OF CHEMICAL PAPERS. Physiological Chemistry. Determination of the Composition of the Different Proteins of Ox and Horse Serum by the Method of Van Slyke. PERCIVAL HARTLEY (BiocAem. J. 1914 8 541-552).-The author has separated the proteins of ox and horse serum and estimated the ammonia- melanin- cystine- arginine- histidine lysine- and residual amino- and non-amino-nitrogen present in each compound by van Slyke’s method (A. 1911 ii 944). The conspicuous differ- ences existing between serum-albumin and serum-globulin with re- gard t o their content of cystine diamino-acids (particularly lysine) melanin and ammonia are advanced by the author as additional evidence controverting Moll’s statement of a transformation of eerum-albumin into serum-globulin occurring in warmed blood serum (compare Bywaters and Tasker A.1913 i 1399). On thePHYSIOLOGICAL CHEMISTRY. i. 1207 other hand the similarity of the figures obtained for the various globulins supports the views of Chick (this vol. i 1145) regarding the close relationship existing between euglobulin and $-globulin. H. W. B. Influence of Excessive Water Ingestion on Protein Meta- bolism. JOHN BOYD ORR (Biochern. J. 1914 8 530-540. Compare Fowler and Hawk A. 1910 ii 625).-A series of experiments carried out on men-shows that the excessive ingestion of water pro- duces an increased excretion of urinary nitrogen due chiefly to an increase in the elimination of ammonia and urea. The action is not however to be regarded as a mere flushing out of waste products from the system because i t is found that the most marked rise in the urinary nitrogen after water drinking occurs on a low protein diet whilst when the subject is on an excessively high protein diet where a large amount of nitrogenous end-products would be pre- sent in the system the smallest rise occurs in the total urinary nitrogen.I n the latter case although during the period of ex- cessive water ingestion the total urinary nitrogen remains almost stationary the absolute amount of urea and the percentage of the total nitrogen excreted as urea bot,h increase. This result which is obtained in all the experiments shows that the main effect of excessive water drinking is a stimulation of the catabolic processes of metabolism. Since on returning to a normal water consump- tion a retention of nitrogen is observed the period of excessive water ingestion is also attended by a stimulation of the anabolic phases of protein metabolism.The appearance of creatine instead of creatinine in the urine during the period of excessive water drinking as recorded by Fowler and Hawk (Zoc. cit.) was not observed. A decrease in the fzecal nitrogen indicating a more complete utilisation of the protein of the food is another of the beneficial effects accompany- ing copious water drinking. H. W. B. Physiology of Reproduction in the Domestic Fowl. IX. Effect of Corpus Luteum Substance on Ovulation in the Fowl RAYMOND PEARL and FRANK M. SURFACE (J. Biol. Chern. 1914 19 263-278).-The desiccated fabfree substance of the corpus luteum of the cow when injected in suspension in proper dosage into an actively laying fowl immediately inhibits ovulation. The duration of this effect varies with different birds from a few days to two to three weeks. After the bird begins ovulating again the laying goes on unimpaired. The same effect is produced by the injection of extracts of the lutear substance either intravenously o r intra-abdominally. The active subst,ance which produces the inhibition is inactivated by boiling. H. W. B.