The results of examinations of members of a large Tyrolian family tree with primary band-shaped corneal dystrophy and other hereditary corneal leasons are reported. Corneal lesions occurred in 16 family members. In three male members, the primary band-shaped corneal dystrophy is associated either with parenchymal opacification and endo-epithelial dystrophy or epithelial dystrophy or with parenchymal opacification and epithelial dystrophy. In some cases, various corneal dystrophies (parenchymal opacification, endo-epithelial dystrophy, cornea guttata, epithelial dystrophy, band-shaped nasal corneal dystrophy) exist without band-shaped corneal dystrophy. A polyphenic gene is responsible for the manifestation of the various corneal lesions. The occurrence of typical primary band-shaped corneal dystrophy only in male family members can be explained by sex-linked inheritance. Because of some flutuations in the expression, the primary band-shaped corneal dystrophy can only be manifested slightly on the nasal border. The hereditary character of the occurrence of the primary band-shaped corneal dystrophy and of the closely related other corneal dystrophies together with the already in 1974 observed association with keratokonus is stressed. Our observations show the variety of the manifestations of a polyphenic gene in the corneal region.