DISTRIBUTION OF DDO GALAXIES

We have examined the distribution of DDO galaxies on the sky and their relationship to normal galaxies. The results appear to contradict the universality of the luminosity function for galaxies. They also indicate that DDO galaxies are preferentially found in the vicinity of normal galaxies, but not uniformly in that they tend to avoid clusters. This may be due to the dependence of distribution upon morphological type. © Royal Astronomical Society.