REPORT ON GRASSES AND FORAGE PLANTS. 191 
tract a substance was precipitable by acids similar in external appear- 
ance to the Holzgummi, it seemed of interest to determine whether, by 
following the exact treatment described by Thomsen, the same sub- 
stance could be isolated from the grasses. Experiments in a qualitative 
way with Sorghum nutans and Bromus unioloides showed that the very 
same Holzgummi is contained in the grasses that Thomsen found in the 
various woods. Although the precipitate from our original alkali ex- 
tract was very dark colored owing to various albuminoid and coloring 
matters, the precipitate of Holzgummi from the soda extract after pre- 
vious treatment with strong ammonia was quite colorless, and possessed 
all the properties and showed all the reactions of Thomsen’s substance. 
As the Holzgummi is therefore not peculiar to wood the name seems 
inappropriate, and our previous designation of the group as amylaceous 
cellulose is for the present, at least, more desirable. 
The fact that sodic hydrate in 2 per cent. solution is able to extract 
this definite substance from grasses led to an inquiry as to what effect 
2 per cent. sulphuric acid would have after such treatment. Would 
it extract by conversion to dextrin and glucose as much matter as in 
the earlier application of the reagent, or would it extract only enough 
to make the total of the two extracts, sodic hydrate and sulphuric acid, 
alike in each instance, the crude fiber remaining always constant? 
From experiments the latter seems to be the case, as may be seen from 
the following results obtained with the sorghum and bromus mentioned 
above: 
Sorghum nutans gave, when treated first with 2 per cent. sulphuric 
acid, 27.25 per cent. of extractive matter, and on subsequent treatment 
with sodic hydrate, 14.44 per cent., a total of 41.69 per cent. When this 
treatment was reversed and sodic hydrate used first the extracts were, 
g sodic hydrate, 35.00; (2) sulphuric acid 5.24 per cent.; a total of 40.24. 
romus unioloides gave similar results, and the two may be tabulated 
as follows: 
Sorghum nutans. 
Per cent. 
First extraction with sodic hydrate. 35.00 
Second extraction with sulphuric 
HST pe alaiaoetes Dee Re ae 
: Per cent. 
First extraction with sulphuricacid. 27.25 
Second extraction with sodic hy- 
HST TEE «Set ESS Bae segs Sears Fe 
Total extracted matter...... 41.69 Total extracted matter... . 40,24 
Bromus unioloides. 
First extraction withsulphuricacid. 23.74 | First extraction with sodic hydrate. 34.12 
Second extraction with sodic hy- Second extraction with sulphuric 
MEAG soe cote se So oct antacwes 13.138 RL sos ee eee ee ae A Sada 4.34 
Total extracted matter...-.. 36.87 Total extracted matter...... 38.46 
It is seen that by either method the total amount extracted remains 
very nearly constant, but that there is a substance which can be ex- 
tracted by either sodic hydrate or sulphuric acid. What this suab- 
stance is, of course, is not definitely known; but as sodic hydrate gives 
us the extractive in a form certainly nearer its original structure, the 
treatment of the grass with that reagent before the application of 2 per 
cent. sulphuric acid seems to be advisable in future grass analyses, and 
in fact in the analyses of any plant where the presence of starch in quan- 
tity does not require removal by acid. 
ANALYSIS OF THE ASH.. 
For the ash anaJysis about 30 grams of the air-dry and coarsely cut 
grass were charred at a heat below redness, an unavoidable glow in 
