I9I3] /. K. Phelps 89 



Soy beans, meat meal and skim milk increase the digestibility of 

 the carbohydrates of the corn with which they are fed. Meat meal 

 and skim milk increase the apparent digestibility of the fat, and 

 decrease the digestibility of the crude fiber of the corn with which 

 they are fed, the results being digestion coefficients of more than 

 100 and less than nothing. 



The acidity of normal urine. Howard D. Haskins. (Labor- 

 atory of Physiology and Biochemistryj Western Reserve Medical 

 College, Cleveland, O.) Certain modifications of Henderson's 

 method were suggested. Permanent color Standards were proposed 

 for the ränge of acidity determined by paranitrophen'ol, A report 

 was made of a study of variations of acidity in 24 hour samples and 

 in fractional samples, i. e., the day's urine collected in five periods. 

 No relation of concentration of urine to acidity was noted. The 

 effect of diet was slight. Night urine was distinctly acid in 50 per- 

 cent of the cases, and morning urine (breakfast to 11) was of very 

 low acidity in 50 percent of the cases. Sweating seemed to have a 

 marked effect in causing higher acidity. 



Sunlight and health. Wilder D. Bancroft, (Cornell Uni- 

 versity, Ithaca, N. Y.) It is usually considered that plenty of sun- 

 light is beneficial to health but Woodruff considers it harmful, espe- 

 cially in the case of tuberculosis. This discrepancy becomes less 

 serious if we consider how light acts. The primary action of light 

 is to tend to eliminate the substance which absorbs it; the primary 

 action is a destroying one. On the other band we get a secondary 

 eüfect with living matter, which is or may be a stimulating one. 

 Strychnine is beneficial in small quantities and toxic in large ones. 

 When studying the effect of light on organisms, one should differen- 

 tiate the two effects. 



The nature of humus and its relation to plant life. S. L. 

 JoDiDi. {Office of Physiological and Fermentation Investigations, 

 Bureau of Plant Indiistry, U. S. Dep't of Agricultiire, Washington, 

 D. C.) See page 17. 



The importance of food accessories as shown by rat-feeding 

 experiments. F. C. Cook. (Animal Physiological Lahoratory, 

 Buerau of Chemistry, U. S. Dep't of Agricultiire, Washimgton^ 

 D. C.) Twelve white rats were fed on a basal diet of protein, fat, 



