Kiithne and Chittenden— Peptones. 235 
On account of the large percentage of ash and the large amount 
of sulphates, the sulphur of the organic matter was not determined. 
Percentage composition of the ash-free substance. 
Average. 
Cie ee 47°52 47°83 47°69 are seat 47°68 
Neier stn 2 701 7-01 7-07 Ee aes 7:03 
IN ee a Baer eee amare 16°57 16°80 16°68 
Antipeptone (E). 
In order to obtain a still purer preparation and especially to free it 
from the large percentage of ash, a portion of antipeptone (D) was 
dissolved in boiling water after the first treatment with ether, then 
when cold the solution was acidified with sulphuric acid to such an 
extent that it contained 6 per cent. of acid and precipitated with a 
large excess of phosphotungstic acid. The precipitate, after the 
manner already described under amphopeptone (B), was washed thor- 
oughly with dilute sulphuric acid and then with water, finally de- 
composed with baryta, the barium-peptone precipitated with alcohol, 
washed, the alcohol driven off by heat, the aqueous solution of the 
compound exactly decomposed with sulphuric acid, the solution con- 
centrated after the addition of a few drops of ammonia, precipitated 
with alcohol, dissolved again in water, concentrated with the addi- 
tion of a little acetic acid, again precipitated with alcohol, and the 
product so obtained treated thoroughly with alcohol and ether in the 
same manner as preparation D, and finally dried in the same manner 
as that. The substance so prepared, was lighter colored than the 
preceding, not quite so hygroscopic, and in drying gave scarcely any 
odor. 
The analysis of the product is shown in the accompanying table. 
Antipeptone (F). (Gland peptone.) 
This peptone was obtained as a bye product in a preparation of 
trypsin from 1,000 grams of dry pancreas and was formed wholly 
from the albuminous bodies of the gland substance, after extraction 
with alcohol and ether. It is not probable that the peptone con- 
tained, in any considerable quantity, any products from the digestion 
of elastin, since the elastic tissue could have been but little altered 
under the conditions in which the self-digestion of the gland took 
place during the preparation of the infusion, and furthermore there 
would have ben needed for solution in the latter, a finer subdivision 
