MODERN FEEDING OF PIGS. 
311 
unexpected changes in many respects, and it is now evident 
that the form of skull does not rest merely upon heredity. 
Only a predisposition to a certain form of skull is transferable 
from parents to their offspring, but whether exactly the same 
form will be transmitted depends to a greater extent upon the 
nutrition, and but little less upon the employment of the 
muscles of the head and neck. It is not only important that 
the nourishment be abundant and well selected, but it is also 
necessary that the individual be in a healthy condition, and 
his digestive apparatus in such working order as to be able to 
utilize the offered food equally well. This is plainly seen by 
comparing skulls from animals which were healthy and grow¬ 
ing vigorously, with those which received the same advanta¬ 
ges of nutrition, but were suffering with a chronic disease. 
Continued weakness, caused either by disease or insufficient 
food, produces a long slender skull, while the skull from a 
strong pig shows a remarkable expansion in its latitude and 
altitude. The following reproductions, taken from originals 
in the agricultural musuem at Berlin, will illustrate this point: 
Fig. III. 
Skull of a three months old pig, which died 
from tuberculosis, % natural size. 
{After Nehring). 
Fig. IV. 
Skull of a two months old healthy and well 
fed pig, % natural size. 
{After Nehring). 
