Explanation

Gk; Phaios = brown, Phyton = plants, Phaeophyceae cell contains more than one parietal chromatophores. The chromatophores contain chlorophyll-a and c $\beta$-and $\alpha$-carotenes and xanthophylls. Besides, they contain large amount of brown coloured xanthophyll-fucoxanthin, which masks the green colour of chlorophylls and that is why these algae appear brown in colour