COMPOSITION IN SUCCESSIVE STAGES. 215 
tion of this substance, probably due to unavoidable loss 
of lower leaves, but not to a resorption or metamorphosis 
in the plant. 
3. Hat is formed most largely at the time of blossom. It 
ceases to be produced some weeks before ripening. 
4, The formation of Albuminoids is irregular. The 
greatest amount is organized during the 4th period, (after 
blossoming.) The gain in albuminoids within this period 
is two-fifths of the total amount found in the ripe plant, 
and also is nearly two-fifths of the entire gain of organic 
substance in the same period. The absolute amount or- 
ganized in the Ist period is not much less than in the 4th, 
but in the 2d, 3d, and 5th periods, the quantities are con- 
siderably smaller. 
Bretschneider gives the data for comparing the produc- 
tion of albuminoids in the oat crop examined by him with 
Arendt’s results. Taking the quantity found at the con 
clusion of the 1st period as 100, the amounts gained during 
the subsequent periods are related as follows: 
PERIODS. 
T. Ii. II. (QL & IIL) IV. (i, TI & IV.) V. 
PATENGTs a= cle sie s0 100s 6%; 46... :@is) 120 233) 36 
Bretschneider ...100 ? ? (165) 62 (227) 3% 
We perceive striking differences in the comparison. fu 
Bretschneider’s crop, the increase of albuminoids goes on 
most rapidly in the 3d period, and sinks rapidly durmg 
the time when in Arendt’s plants it attained the maximum, 
Curiously enough, the gain in the 2d, 3d, and 4th periods, 
taken together, is in both cases as good as identical, (233 
and 227,) and the gain during the last period is also equal. 
This coincidence is doubtless, however, merely accidental. 
Comparisons with other crops of oats,examined,though very 
incompletely, by Stéckhardt, (Chemischer Ackersmann, 
1855,) and Wolff, (Die Erschépfung des Bodens durch die 
Cultur, 1856,) demonstrate that the rate of assimilation is 
not related to any special times or periods of develop ent, 
