Report of 2 pedigrees during 4 and 3 generations respectively, whose members have been investigated by the author personally with the splitlamp. In addition to these pedigrees some more smaller families were examined and compared with communications from the literature. All this leads to the assumption that the lacunar type of irisstructure with its irregular and more peripherically situated irisfrill, as a result of increased reabsorption of the iridopupillary membrane, is an autosomal trait, which behaves like a single dominant. The iris with a more continuous boundery layer and an irisfrill which is situated nearer to the pupil is recessive. It will be necessary in future to settle the genetic background of the subtypes of both contrasttypes, mentioned above.