734 
Journal of Agricultural Research 
Vol. XXXI, No. 8 
seemed more desirable than a commercial product used by Horton 
m- 
Hemicellulose, or acid hydrolyzable material, was determined by 
boiling the residue from the starch digestion with 100 c. c. of 2.5 per 
cent H 2 S0 4 for 1 hour, with a reflux condenser. The solution was 
filtered and the filtrate neutralized with NaOH and clarified as above. 
The acid-hydrolyzable substance was determined by the Defren- 
O’Sullivan method and expressed as dextrose. 
Total nitrogen was determined by using about 0.7 gm. of material 
from the composite samples. The Kjeldahl method as modified by 
Arnold-Gunning, with the further modification to include nitrates by 
the addition of salicylic acid, was used, and the results expressed as 
total nitrogen. 
DISCUSSION 
The dry weight of the total plants after germinating for one day is 
greater than the dry weight of the original seeds, but during the second 
and third day a considerable loss takes place. Doyer (If) points out 
that the chief changes in the first day of germination is the absorption 
of water, and little heat is given off. Tne greatest warmth is devel¬ 
oped during the third and fourth days. Cribbs found by measuring 
the C0 2 given off during germination 4 that the respiration on the 
second day was about three times as great, and on the third day 
about five times as great as the first day. This small amount of 
respiration and loss of weight, with the gain in weight due to the 
hydrolysis of starch, may account for the slight increase in weight. 
The seed has the most rapid loss in weight between six and nine days, 
which is a period of rapid growth, before the plant has developed 
far enough to make carbohydrates rapidly. It is, however, increas¬ 
ing its ash content. The lowest dry weight is reached at 12 days, 
after which the anabolism is more rapid than the katabolism. The 
dry weight of the plumules seems to be always greater than the dry 
weight of the roots. 
Tne use of storage fat by the seed has been studied extensively 
on fatty seeds. A comprehensive history is given by Miller (32 ). 
Wasniewoski (J+8) reports an increase in the amount of fat during 
the germination of wheat seedlings and suggests that some is formed 
from starch. This is in disagreement with most of the earlier work 
and with results reported here, which do show, however, that the 
fats of the seed are used more slowly than the other reserve foods in 
the seed. Spoehr (37) says “fats are important, especially in the 
development of seedlings.” The other extract decreases slowly in 
the total plants up to six days, but at nine days a decided increase, 
particularly in the plumules, takes place. Tins is probably due to 
the chlorophyll. By referring to Table IV or Figure 2, it will be 
noted that at nine days the plants have about estalnished the normal 
amount of ether extract, since the percentage in the plumules and 
roots remains about constant from this point on. The roots have a 
higher percentage of fat in the young stages than in older stages, 
which suggests that some of the fat may be translocated as fat and 
is later used by the root. 
* Cribbs, W. J. the effect of freezing seeds on the respiration and catalase activity of seed¬ 
lings. 1923. [Unpublished thesis, Univ. Chicago.] 
