a_.

Many different hypotheses have been put forward concerning the mode of
transformation of fats into carbohydrates, and the changes which take place
in oily seeds during their germination have been carefully studied by many
investigators. The following seem to be fairly well established facts.
First, that fats as such may be translocated from cell to cell, since
cell-walls and cell protoplasm seem to be permeable to oil if it is a
sufficiently fine emulsion; or they may be hydrolyzed into glycerol and
fatty acids and translocated from cell to cell in these forms and
recombined into fats in the new location. Second, that fats are formed from
glucose in some plants, from sucrose and from starch in others, and from
mannite and similar compounds in still other species. Third, that in
germination the fatty acids are used up in the order of their degree of
unsaturation, those which contain the largest number of double-bond
linkages being used first, and the saturated acids last of all. Fourth,
that the sugar produced by the oxidation of fats is derived either from the
glycerol or from the fatty acids of the fat, depending upon the nature of
the latter. If the fat is saturated, the glycerine is converted into sugar
while the fatty acids are oxidized; but if the fat contains large
proportions of unsaturated acids, these contribute to the formation of
sugar.

Recent studies seem to show that in the animal body fats serve an important
function in connection with the production of antibodies to disease germs.
But there is as yet no evidence to show that fats and oils have any similar
function in plant tissues. The fact that they are found almost wholly in
the storage organs of plants seems to indicate that their use as food
reserve material is their principal, if not their sole, function in the
plant economy.

B. THE WAXES

Waxes are most commonly found in or on the skin of leaves or fruits. They
are similar to fats in chemical composition, except that, instead of being
glycerides, they are esters of monohydric alcohols of high atomic weight.
The term wax, when used in the chemical sense, has reference to this
particular type of esters rather than to any special physical properties
which the compound possesses, and both solid and liquid waxes are known.

Carnauba wax, found on the leaves of the wax-palm (_Copernicia cerifera_)
contains ceryl alcohol (C_{23}H_{53}OH) and myricyl alcohol
(C_{