author(s) : Abdel-Fattah M. Rizk, Husseiny A. H. Elgendy and Fahem A. Ahmed

The family Adiantaceae (Ptridophyta) has 56 genera and 1150 species (Boulos, 1999).
Twenty-one flavonoid glycosides (chiefly flavonol glycosides) were found in the fern genus Hemionitis (syn. Gymnopteris), including derivatives of kaempferol, quercetin, apigenin and luteolin (Giannasi and Mickel, 1979). Farinose exudates on fronds of Notholaena species are known to consist of flavonoid aglycones.
These are predominantly methylated flavones and flavonols, sometimes chalcones and dihydrochalcones.
Flavonols with unusual properties excreted as major farina components by some species, were derivatives of methylated flavonols, esterified in position 8 with butyric or acetic acids.
They occur as twin-pairs, some with very great differences in proportions. Their presence in a group of species within the genus has chemotaxonomic implications (Wollenweber et al., 1978).
The family Adiantaceae is represented in Egypt by 4 genera and 6 species (Boulos, 1999)