You must have missed my reply. The first leaves on a flowering plant are not
true leaves, and they are not evolutionary vestiges of anything. They are
called cotyledons, or seed leaves. They are the endosperm that was inside the
seed. They contain starch and/or sugar, and are there to feed the baby plant
until it has enough roots & leaves to feed itself. If you want an analogy from
the animal kingdom, it is the equivalent of the yolk sac on a baby fish.
Go get yourself some dried lima beans. Put them in a jar next to the glass,
backed up by some wet paper towels. Leave them in a well-lit spot for a week or
so & watch what happens.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)