THE RELATION OF DIET TO DISEASE 433 
be caused by an improperly balanced diet, or by the 
addition of an excess of calcium to the diet of an animal 
whose body fluids were unable by reason of previous 
faulty diet or other disorder, to hold it in solution. In 
young animals the calcium demands are much higher than 
in adults, a need met in the high calcium content of breast 
milk, a content in excess of almost every other food, but 
apparently just sufficient to maintain calcium equilibrium. 
After it is weaned the young animal frequently shows 
disorders of its inorganic metabolism. Herter estimated 
that a child should store at least 0.1 gram of calcium daily 
and he described many cases of arrested bone develop- 
ment occurring during infancy and early childhood, 
because of an inefficient assimilation of calcium. One 
case, probably of this character, was found in a Hama- 
dryas Baboon {Papio hamadryas) a typical example of 
infantilism. The animal was an adult male about half 
the size of an adult female. His skin was fine and more 
delicate than normal, the bones were small and slender, 
contour of body was that of a young animal, genitalia 
were imperfectly developed, thyroid gland apparently 
normal, gastrointestinal tract atrophic, associated was 
a slight arthritis, portal cirrhosis of liver and 
diffuse nephritis. 
First among the results of inorganic insufficiency in 
youth stands Rickets. This disease occurs in children 
starting usually at about the sixth month and continuing 
with irregular remissions for several years. The bone 
changes, which are the most prominent, are always 
associated with more or less severe anemia, a general 
lowered resistance and flabby musculature. The excre- 
tion of calcium is very high in the feces and low in the 
urine. There is a frequent negative calcium balance 
dependent upon the great loss in the feces. Healing is 
preceded by a hyperretention of calicum and a relative 
increase in the urinary calcium. The excessive loss of 
calcium in the feces is not brought about through the 
