.( 16 ) 

 METHODS USED IN THE ANALYSIS 



The eggs after removal of the shells were beaten and then dried 

 at about 40 C. They were then ground to a powder and the final 

 determination of the moisture of the powder made in the usual way. 



The fat of the egg was extracted with chloroform, the extraction 

 of 1.5 to 2 grams of the egg powder being carried on for twenty-three 

 hours. 



The nitrogen was determined by the usual Kjeldahl method, the 

 factor, 6.25, being used in the calculation of the amount of protein. 



The total phosphorus was determined as Mg 2 P 2 O 7 , using H SO 4 

 and NH 4 NO 3 in the digestion. 



SUMMARY 



1. The work on the coloring of the parts of the egg by feeding 

 dyes to the hen indicates that the fat found in the albumen region of 

 the incubated egg is derived not wholly from the yolk, but from an- 

 other source, the albumen itself. 



2. The percentage of fat in the yolk of the weak chick is in some 

 cases less and sometimes more than in the yolk of the strong chick. 



3. The weak chick is equally as rich in phosphorus as the strong 

 chick. 



4. The phosphorus content of the egg varies but little. 



5. There is no increase in the phosphorus content of the egg when 

 the hen is fed inorganic phosphorus. 



6. Hens on range do not produce eggs different in composition 

 from those on bare yard. 



7. There is a variation in the eggs of individual hens in the con- 

 tent of protein and in the content of fat, but the eggs produced by 

 each individual are quite constant in composition. 



8. The sum of the percentages of the fat and of the protein in 

 eggs varies but little. 



9. In feeding a ration high in fat, or a ration high in protein, there 

 is no material change in the characteristics of the hen as regards the 

 amount of fat and protein in the egg. 



10. There seems to be no relation between the protein or fat con- 

 tent of the egg as regards its hatching power or the vigor of the 

 young chick. 



ACKNOWLEDGMENT 



I wish to express my thanks to Professor G. W. Cavanaugh for his 

 direction of the work and his interest in the problem, and to Professor 

 C. A. Rogers for his co-operation in this investigation. 



I am also indebted to Professor J. E. Rice for his helpful sugges- 

 tions, and to Mr. W. L. Lyon for his care in the selection of all samples. 



