The anthocyanin, anthocyanidin and proanthocyanidin content of 52 induced barley mutants with altered anthocyanin pigmentation in different organs of the plant has been investigated. Comparing these mutants no correlation between the amount of anthocyanin in the plant and the amount of proanthocyanidin in the dry grains is found. The proanthocyanidins of the lemma, palea, pericarp, testa and aleurone of Bonus, Foma, Kristina, Herta, Balder and 37 a n t mutants yielded upon hydrolysis delphinidin and cyanidin. In 50 of the mutants belonging to at least 16 gene loci only anthocyanin synthesis is impaired. In mutant ant 13-13 a step in the biosynthetic pathway leading to anthocyanins, catechins and proanthocyanidins is blocked.