1895.) Fluorine as a Test for the Fossilization of Animal Bones. 721 
Magnesium phosphate, . ; Peet A 13 
Calcium fluoride, Ce et ge -57 
93.63 
The specimen said to be fragments of the human pelvis con- 
sisted of a disk of perhaps an inch in diameter and a quarter 
of an inch thick, pieces of what appeared to have been another 
disk similar to the first, and a quantity of coarse powder. 
That the-two were not identical in composition is evident from 
the difference in the loss on ignition, the solid pieces having 
given 25.05 and the powder 14.20 per cent. 
As the determination of fluorine was a special object in this 
investigation, I decided to use only the solid pieces of the bone, 
as this would afford a better means of comparison with the 
mylodon bone. This was accordingly done, and the following 
was the result of the partial analysis which was carried out 
on the same sample in which the fluorine was determined : 
Moisture, . i 5 : ; ; 3.62 
Organic matter, . : : 21.43 
Tron (and alumina) phosphate, gone SA 
Lime (Ca O), ‘Eo eo. ae 
Phosphoric acid P, 0, ; í : 20.77 
Fluorine, . $ ‘ ; 38 (=.78 Ca F;,) 
It was impossible to determine the carbonic acid. The in- 
soluble residue was slight, but was not determined. 
Deducting the moisture and organic matter, we should get 
- for the composition of the ash of the mylodon :— 
Calcium carbonate, . : A ‘ ‘ ; . 13.14 
Calcium phosphate, . oea r R 
Iron (and alumina) phosphate, a ee: 
Calcium fluoride, : i i : : ‘ 88 
We have not sufficient data for making a similar complete 
-calculation in the case of the human bone, but we can give 
