These are yellow green algae which contain chlorophyll ‘a’ and chlorophyll ‘e’ or ‘c’. Besides chlorophylls they possess xanthophylls and beta carotene. The class xanthophyceae is divided into four orders: Heterochloridales, Heterococcidales, Heterotrichales and Heterosiphonales.
1. Heterochloridales
   Examples: Heterochloris, Misclococcus, Chlorogloea
2. Heterococcidales
   Examples: Halosphaera, Chlorothecium, Chlorobotrys
3. Heterotrichales
   Examples: Tribonema, Heterodendron
4. Heterosiphonales
   Examples: Botrydium, Vaucheria