  We present a statistical study of a very large sample of HII galaxies taken
from the literature. We focus on the differences in several properties between
galaxies that show the auroral line [OIII]l4363 and those that do not present
this feature in their spectra. It turns out that objects without this auroral
line are more luminous, more metal-rich and present a lower ionization degree.
The underlying population is found to be much more important for objects
without the [OIII]l 4363 line, and the effective temperature of the ionizing
star clusters of galaxies not showing the auroral line is probably lower. We
also study the subsample of HII galaxies whose properties most closely resemble
the properties of the intermediate-redshift population of Luminous Compact Blue
Galaxies (LCBGs). The objects from this subsample are more similar to the
objects not showing the [OIII]l 4363 line. It might therefore be expected that
the intermediate-redshift population of LCBGs is powered by very massive, yet
somewhat aged star clusters. The oxygen abundance of LCBGs would be greater
than the average oxygen abundance of local HII galaxies.
