Morgan (1958) identified galaxies which seemed to have such strong nuclei that they appear to be nearly stellar on photographs, although it is clear on close inspection that these are not point sources. These were designated as ``N'' (for ``nuclear'') galaxies. Several of these have turned out to be Seyferts or BLRGs, the latter in particular as these show no structure in their stellar components.

Adapted from B.M. Peterson An Introduction to Active Galactic Nuclei, Cambridge University Press, (1997)