The distribution of C-banded heterochromatin was determined in an inbred line of Dasypyrum villosum. Practically no difference in chromosome morphology or band distribution could be observed within the chromosomes of the same pair. Heterochromatin bands, revealed by Giemsa banding, were characterized by means of their differential reaction to fluorochromes, silver staining and in situ digestion with different restriction endonucleases. The results clearly indicate that in D. villosum two different classes of heterochromatin with different chromosomal local-ization exist: one is evidenced by both C-banding and DAPI staining and has mainly telomeric distribution, the other is evidenced only by C-banding and has mainly centromeric distribution.