1. Appreciable amounts of fluorine is retained by bovines and
rats on rations to which fluorine has been added. Bovines retain
approximately 0.2 grm. and rats 1 mgm. of F per day under the
conditions of the experiment.
2. The percentage F occurring normally in ash of rats varies
from 0.039 to 0.05.
3. The ash per 100 grams empty weight in rats is increased by
4. Fluorine causes a decreased retention of both calcium and
phosphorus in rats, a slight increase in calcium retention and a pronounced decrease in the phosphorus retention of bovines.