Most plants invest considerable resources in
cytoplasmic inclusions such as starch, tannins,
silica bodies, and calcium oxalate crystals in
some of their cells. Calcium oxalate crystals are
widespread in fl owering plants, both dicotyledons
and monocotyledons, indicating their importance
in basic processes of growth and development. It
has been proposed that calcium oxalate crystals play
a role in ion balance, plant defence, tissue support,
detoxifi cation, and light gathering and refl ection
(1). In some plants crystals have more specialised
functions, such as promoting air space formation
in aquatic plants or helping to prevent herbivory,
although many plants containing calcium oxalate
crystals are eaten by birds and animals, such as