28 



corn meal and wheat middlings, feed two or three times a day in-, 

 order to fatten them and sell them as soon as possible. 



Here is the most violent contrasts known in low vitality (Fig. 9). 

 A crow head, sunken eye, poor-bodied, irregular-feathered individual 

 with long thin shanks and toes. 



Figure 10. High vitality hens used in the breeding experiment. 



Figure 11. Low vitality hens used in the breeding experiment. 



