"CERO A ia 
1920] 
DUGGAR—VALUE OF FOOD RESERVE IN COTYLEDONS 293 
TABLE I 
THE EFFECTS OF THE RESERVE FOOD SUPPLY ON THE GROWTH OF 
SEEDLINGS 
Field corn, 10 plants, Canada field peas, 10 plants, 
average of duplicate cultures average of duplicate cultures 
Cult. 
no. : ; 
Time of Total Time of Total 
excision of green wt., || Cult. excision of green wt., 
endosperm grams no. cotyledons grams 
1 After 2 days 32.72 1 After 2 days 5.75 
2 After 5 days 30.18 2 After 3 days 10.12 
3 After 7 days 34.02 3 After 4 days 17.70 
4 After 8 days 30.11 4 After 5 days 19.82 
5 After 9 days 36.11 5 After 7 days 24.30 
6 After 10 days 36.98 6 Control, uncut 25.51 
ledons was done in all cases with the greatest care, so that no 
injury to the seedling would result. The excision was made 
at a point beyond the stalk of the cotyledons. In the case of 
corn the results are a little irregular. Nevertheless, there is 
the suggestion that the removal of the main carbohydrate food 
supply is not so important a factor in depressing the growth of 
the young plant. From subsequent incidental experiments I 
am convinced that there is some effect, but it is neither so marked 
as in the case of the peas nor does it seem to be so permanent, 
that is, the effect is not so striking during the further develop- 
ment of the plant. 
During the summer of 1919' an attempt was made to sub- 
stitute for the loss of the cotyledons in the case of the peas by 
the addition of certain organic nitrogen-containing nutrients, 
and especially by the addition of glycocoll, alanin, sodium 
asparaginate, and sodium nucleinate. These experiments were 
carried out under the most favorable conditions for the growth 
! This series of experiments and other supplementary studies not yet concluded 
were carried out at the Coastal Laboratory of the Carnegie Institution of Washing- 
ton, Carmel, California, and the writer takes this occasion to acknowledge his in- 
debtedness to the Director of Botanical Research, Doctor D. T. MacDougal, for 
placing at his disposal the facilities of the laboratory and d his cordial coóperation. 
