SECT. 



I] 



PHYSICO-CHEMICAL SYSTEM 



243 



centage of mineral substances than the rest. The dry-weight figures 

 merely demonstrate again the approximate equality of the protein 

 and fat. 



Before we proceed to consider the parts of the tgg in separation, 

 the question of individual and racial differences must be taken up 



Table 3. Individual differences between hen's eggs, 

 Malcolm's figures (1902). Averages of individual hens. 



Breed unknown 



Italian hens (fed on maize and barley) 



From one hen 



From one hen 



Iljin's figures (19 17). 



Houdan... 

 Orpington 

 Plymouth Rock 

 Rhode Island .. 



Table 4. Race differences in hen's eggs. 



Leveque & Ponscarme's figures. 



16-2 



