Peculiar Galaxies by D. W. Dewhirst Ph.D. ,of the Cambridge Observatories
The study of extragalactic nebulae has revealed a pattern of shapes and structures, which is probably related to the scheme of evolution of galaxies. But many examples do not fit into the established pattern. Some, but by no means all, of these are sources of radio emission. Are these galaxies in collision? Or do they represent an unsuspected stage of evolution?
