5.5. The K-System

This is the most numerous group of all and comprises 23 galaxies having a great diversity in appearance. Their spectra, however, indicate that the principal contribution to the total luminosity in the blue-violet region is probably from K-type giant stars. The K-systems are listed in Table V, and they all have one property in common: the major part of the luminosity originates in a brilliant, amorphous central region.