Dec. 15,1925 
Nitrogen Metabolism in Etiolated Corn Seedlings 
1157 
Table IV. — Acidity percentage of the various seedling extracts 
[Twenty cubic centimeters of extract used in each case] 
No. 
Conditions of germination 
Weight of 
oven-dried 
seedlings 
corre¬ 
sponding 
to extract 
used 
N/10 NaOH 
used for 
neutraliza¬ 
tion 
Average 
Dura¬ 
tion 
Substratum 
Tem¬ 
pera¬ 
ture 
Treatment 
Days 
° C. 
Grams 
C. c. 
C.c. 
1 
3 
Sand. . _ 
27 
None_ 
0.3706 
0.91 
0.91 
2 
3 
_do_ 
27 
___ _do_ 
.3706 
.91 
} 
3 
4 
do. . _ 
27 
do.— _ 
.3647 
1.24 
1.26 
4 
4 
__ _do_____ 
27 
_ .do_ - 
.3647 
1.28 
} 
5 
2 
Paper__ 
30 
_ ___do.. 
.3737 
.38 
.39 
6 
o 
~ do_.... 
30 
_do_ 
.3737 
.40 
i 
7 
4 
_do_„---__ 
30 
.do.. 
.3726 
.73 
x 
.73 
s 
4 
_do__ 
30 
_ __ do.. 
.3726 
.72 
9 
8 
_do.. -- 
30 
_do__ 
.3752 
1.18 
1.19 
10 
8 
___ _do___ _ 
30 
_do... 
.3752 
1.20 
11 
4 
, do__ 
25 
Uspulum_ _ _ 
[ .3764 
.72 
.71 
12 
4 
_do__ 
25 
_do__ 
| •3764 
. 71 
[ . 3764 
. 70 
13 
g 
do__- 
25 
_do_ 
.3756 
.92 
\ 
.93 
14 
8 
do . 
25 
do.. 
.3756 
.94 
/ 
15 
1] 
do_ 
25 
_do__ 
.3773 
1.07 
1.12 
16 
11 
do . 
25 
... do_ 
.3773 
1.16 
\ 
17 
Ungerminated seed _ 
.3658 
.24 
\ 
.25 
18 
do_ 
.3658 
.26 
; 
Inasmuch as the observation was made by Schulze (19) and others 
that the organic phosphorous compounds present in seeds are gradu¬ 
ally converted into inorganic phosphoric acid, as germination of the 
seeds progresses, the idea suggested itself that the acidity of the 
aqueous extracts of the seedlings might be due to this very reason. 
Although no quantitative analyses of the inorganic phosphoric acid 
occurring in the water extracts of the seedlings were run, repeated 
qualitative tests seemed to point to the fact that the rise in the 
acidity of the seedling extracts is to be attributed at least in part to 
the increase of the inorganic phosphoric acid. 
DISTRIBUTION OF THE WATER-SOLUBLE NITROGEN IN THE SEEDLINGS 
In order to establish the chemical nature of the organic nitrog¬ 
enous compounds met with in the water extracts of the various 
seedlings, tne following experiments were made. Ordinarily 100 or 
50 gram portions of seedling flour were treated with boiling hot 
water and heated on the water bath for 15 minutes, after which 
the whole was centrifuged. The solid residues were treated twice 
more in like manner. The three extracts were now combined, refil¬ 
tered if necessary, and made up, to 1,000 c. c. or 500 c. c. In two 
portions of 25 c. c. each the nitrogen was estimated according to 
KjeldahPs method, which gave the total water-soluble nitrogen (a). 
From 400 c. c. ofthe remaining extract proteins were removed by 
slightly acidifying the extract with acetic acid and adding a 10 per 
