  We infer the redshift distribution of the faint blue galaxy excess (FBE) at
B=23.5 by subtracting the predicted distribution of giant/normal galaxies from
the observed N(z) distribution for all types. This is possible because of the
recent deep {\it Hubble Space Telescope} (HST) WFPC2 morphological number
counts which have convincingly demonstrated that little evolution of the giant
population is seen to B=26.0. The mean redshift of the FBE at B=23.5 is found
to be <z>_{FBE}=0.40 +/- 0.07 with upper and lower quartiles defined by
z_{0.75}=0.58 +/- 0.05 and z_{0.25}=0.28 +/- 0.05, respectively.
  We compare this inferred FBE N(z) distribution to the predictions from three
generic faint galaxy models: dwarf dominated (no evolution), pure luminosity
evolution, and evolving dwarfs. The inferred FBE N(z) distribution strongly
supports a hybrid evolving dwarf--rich model wherein a large population of
dwarfs present at z=0.5 has subsequently faded to obscurity. The total
integrated number density of dwarfs (down to M_{B}=-11) is estimated to be a
factor of 20 times greater than that of E---Sc galaxies and the estimated
fading to be 1.0 < \Delta m < 1.4 mags. Thus, the dwarf population is estimated
to be responsible for ~30% of the luminosity density locally, rising to ~57% at
z=0.5.
