NUTRITION — CHITTENDEN, MENDEL. 20I 



teid diet as found by these investigators were not due to the small amounts 

 of proteid diet taken, but to other causes, since the present investigation has 

 shown that it is quite possible to keep dogs in a condition of physiological 

 and body equilibrium, with maintenance of health, strength, and vigor, on 

 quantities of proteid food and with amounts of non-nitrogenous foods which, 

 according to the statements of the preceding investigators, were insufficient 

 to sustain life. Many interesting results have been obtained, which will be 

 published later. 



Grant No. sy6 ($i,ooo). — Attention has been given to the distribution of 

 the nitrogen and sulphur excreted in the urine of dogs poisoned with hydrazin, 

 for the purpose of determining some of the processes which may take place 

 in deranged metabolism, with the hope of thereby offering an explanation of 

 certain phases of intermediary metabolism. The results indicate that in the 

 distribution of the urinary nitrogen ver}^ little change occurs, but that 

 the neutral sulphur excreted in the urine is increased — in some cases cystin 

 appearing in the urine. Allantoin excretion is not increased by hydrazin, 

 contrary to previous observers, and its appearance in the urine may be 

 explained as a phenomenon induced by starvation, a necessary condition for 

 such experimental animals. Oxalic acid is largely increased. From histo- 

 logical examination of the various organs, it is concluded that hydrazin acts 

 upon the liver specifically, producing in that organ changes in many respects 

 similar to those provoked by phosphorus. This investigation was carried out 

 in the Sheffield Laboratory of Physiological Chemistry by Professor Frank P. 

 Underbill and Mr. Israel S. Kleiner. 



Mendel, Lafayette B., Sheffield Scientific School of Yale University, New 

 Haven, Connecticut. Grant No. 265. Study of the physiology of 

 growth, especially in its chemical processes- (For previous reports see 

 Year Book No. 4, pp. 259, 260, and Year Book No. 5, p. 213.) $2,000. 



A series of papers on chemical studies of growth is in press and in prepa- 

 ration. Those which have appeared are : 



(i) The Inverting Enzymes of the Alimentary Tract, especially in the Embryo. 



(2) The Enzymes Involved in Purine Metabolism in the Embryo. 



(3) The Occurrence of Glycogen in the Embryo Pig. 



The following papers in the series have been prepared : 



(4) The Transformation of Glycogen by the Enzymes of Embryonic Tissues. By 



Lafayette B. Mendel and Tadasu Saiki. (In press November, 1907.) 



(5) The Autolysis of Embryonic Tissues. By Lafayette B. Mendel and Charles 



S. Leavenworth. (In press November, 1907.) 



(6) Changes in the Purine-, Pentose-, and Cholesterol-content of Developing 



Eggs. By Lafayette B. Mendel and Charles S. Leavenworth. (In press 

 November, 1907.) 



The completed researches awaiting publication include investigations on 

 the catalase and lipase of embryonic tissues ; the muscular tissue in em- 

 bryonic life ; the lipoids of embryonic organs ; in addition to studies mentioned 

 in an earlier report. 



