3§4 
Notes. 
flattened and extended laterally, cracks along the edges, and half of it 
continues to lie adpressed to each cotyledon. The surface of con- 
tact between the two is at this stage slimy, as if the material of the 
endosperm had become deliquescent. Later gradually the two 
pieces of endosperm dry up. 
During these changes of form intricate chemical changes take 
place inside the cells. The aleurone-grains gradually dissolve; the 
proteids of which they are composed, viz. globulins and albumoses, 
becoming transformed into peptone and later into asparagin. The 
cotyledons are the organs of absorption, and they take up the latter 
body, which can be extracted from them in crystalline form. The oil 
disappears during the germination, but does not enter the cotyledons 
unchanged. It consists chiefly of ricinoleic acid in combination 
with glycerine, and the first decomposition that is observed is the 
separation of the fatty acid from the other constituent. During the 
early days of the germination the free fatty acid that can be extracted 
from the endosperm increases considerably in quantity. Later on it 
diminishes, and its place is taken by another acid which differs from 
the greasy ricinoleic acid by being soluble in water, capable of 
dialysis, and crystalline in appearance when separated out. Ricinoleic 
acid has been proved by several observers to be capable of such 
a decomposition as this in the laboratory when treated with oxidising 
agents, such as nitric acid or permanganate of potash. This 
crystalline acid makes its appearance a little later in the process than 
the fatty acid, and though absorption of it goes on continuously by the 
cotyledons, the endosperm contains about the same percentage during 
the rest of the germination, while the fatty acid is continually getting 
less in quantity. 
Besides this acid the cotyledons are continually absorbing sugar 
from the endosperm. This arises during germination, only a trace 
being found in the resting seed. There is hardly any doubt that 
its immediate antecedent is the glycerine that comes from the splitting 
up of the oil. Glycerine has been proved to be easily convertible 
into sugar, and though there is sufficient liberated in the decomposition 
of the oil to account for all the sugar formed in germination, none 
of it can be found in the free state either in the endosperm or in the 
cotyledons. 
In the last stage of the germination the thin shell of endosperm left 
only contains a little sugar and a little crystallisable acid. 
