Bui. 561 , U. S. Dept. of Agriculture. 
Plate I. 
Fiq. 1.— Pen 2, Mixed Pen of General-Purpose Breeds. 
On free range; fed a ration without oats. 
Fiq. 2.— Pen 4, Single-Comb White Leghorns. 
On free range; allowed to select their own mash. 
