50G 
The Seed and its Germination. 
great richness in oil that this seed has been selected as the 
most suitable for research. The cells of its endosperm contain 
a number of aleurone grains, which are more complex in their 
nature than those of the lupin, for each has inside its ovoid body 
a crystal or crystalloid of proteid matter, and a small globular 
mass of mineral nature, the globoid (fig. 11). The digestion of 
these proteids proceeds on almost exactly the same lines as in 
the case of the lupin. The matrix of the protoplasmic matter 
in which these aleurone grains rest is saturated with the oil, so- 
that this latter does not occupy spaces in the interior of the 
cells as the cell sap does. This appears to be the way in which 
fatty matter is generally stored. There is no starch or other 
carbohydrate in any appreciable quantity laid up in the castor- 
oil bean, so that the reserves are only proteid and oil. Generally 
in seeds where oil is very abundant this is found to be the case, 
though when there is but little oil starch also may be present. 
In such a seed as this, then, the oil must take a large share 
in the nutrition of the embryo, and being a highly complex body 
it gives rise to a very elaborate series of changes before the food 
for the young plant is made suitable for its absorption. 
In composition, fats are made up of a combination of fatty 
acids, such as stearic or oleic acid, with glycerine. By various 
means, especially by subjecting them to the action of alkalies 
such as caustic potash, or by distilling them with super-heated 
steam, this combination can be broken up, and the glycerine and 
fatty acid can b eseparated from each other. This is the decom- 
position which is brought about in the manufacture of soaps, 
which are the bodies formed when fatty acids are made to com- 
bine with oxides of metals, the most familiar ones being the soda 
and potash soaps. 
The first decomposition which can be traced in the germina- 
tion of the castor-oil bean is this liberation of the fatty acid from 
the glycerine. If a germinating seed be treated with a little 
very weak soda solution, and the extract filtered, the latter is 
found to contain a soda soap, which can be decomposed by the 
addition of a little mineral acid such as sulphuric, when the 
fatty acid separates out as a curdy precipitate. The acid is 
insoluble in water, while the soap, like all soda soaps, is soluble. 
This fatty acid is a thick, greasy fluid, which is incapable of 
dialysing through a membrane such as parchment paper or cell 
wall. 
The decomposition is effected in the seed by the agency of 
another ferment, which, like the tryptic one, exists in the 
endosperm of the resting castor-oil bean in the condition of a 
zymogen. 
