Begonia Registration Handbook - American Begonia Society

An Obtuse apex is an apex that
has an angle between 90º and
180º and has sides that are
reasonably straight with the angle.
If the apex is pointed it is a
sharply obtuse apex and if apex
is rounded off it is a rounded
obtuse apex.
An acute apex is an apex of less than 90º that follows the angle in a
reasonably straight line. If the apex has a point it is a sharply acute
apex and if the tip is rounded off it’s a roundly acute apex.
A caudate apex is one
that has a rounded blunt
end with a fine pointed
tail-like tip.
Emarginate apexes and Retuse
apexes have an indented rounded
tip forming two humps on the tip.
If the humps are deep and narrow
it’s an Emarginate apex and if
flat and broad it’s a Retuse
apex.
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