Germination of Helianthus annuus . II. 901 
The acetyl value for the first three stages averages about twice as great 
as that of the ether extract of the cotyledons at the respective stages. 
It will be noticed that the constants which were determined for the 
ether extract of the hypocotyls and roots for the first three stages have 
a striking resemblance to those of the ether extract of the cotyledons 
during those stages. The results indicate, however, that the changes in 
the oily material during the first two stages consist in a gradual but evident 
breaking down of the higher free fatty acids and glycerides into those of 
lower molecular weight, the saturation of the fatty acids, and an increase 
in the amount of the hydroxyl groups present. During the last two stages, 
however, these changes are rapid and very marked, as indicated by the value 
of the different constants determined. 
Summary. 
1. The acid value of the ether extract of the seed is low, amounting 
to only i-6, and this value remains the same for the oily material of the 
cotyledons until two-thirds of the oily reserve has disappeared from them. 
After that the acid value increases rapidly. There is evidence that the greater 
part of the free acid present in the ether extract at all the stages is composed 
of free fatty acids of high molecular weight which are insoluble in water. 
2. The results obtained indicate that, with the exception of the increase 
in the amount of free acid, no change takes place in the oily reserve remaining 
in the cotyledons until the last stage, when the seedling has become an inde- 
pendent plant. At that stage only 5-3 per cent, of the original oily reserve 
remains in the cotyledons. 
3. The results indicate that the change taking place in the oily material 
of the cotyledons when only 5*3 per cent, of the oily reserve remains, consist 
in a breaking down of the higher fatty acids and glycerides into those of 
lower molecular weight, a partial saturation of the free and combined fatty 
acids, and a marked increase in the amount of free acid. 
4. The amount of oily material contained in the hypocotyls and roots 
remains practically constant for all stages of the seedling examined. 
5. Some of the constants of the oily material of the hypocotyls and 
roots during the first three stages of the seedling have a striking resemblance 
to those of the oily reserve of the cotyledons at those stages. The results 
in general, however, show that during these stages there has occurred a 
gradual but well defined breaking down of the oily material into free fatty 
acids and glycerides of low molecular weight, a marked saturation of the 
fatty acids, and an increase in the amount of the hydroxyl group of the 
oily matter. During the last two stages of the seedling these changes are 
very rapid and very marked. 
Kansas State Agricultural College, 
Manhattan, Kansas. 
