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We carried out follow-up spectroscopy of 178 Case galaxies
in the zone - 16h, and
- +38
,classified in the Case catalog with some code, indicating the presence of
the line [OIII]
5007, and not observed in the previous
follow-up studies. One of the Case candidates shows quasar-like features
in the spectrum.
Nine Markarian galaxies have been observed additionally in the same sky region.
We present the redshifts, equivalent widths and flux ratios of strong
emission lines for 142 galaxies.
In 44 objects we have not detected emission lines (in blue). In half of them
we could detect the common absorption features: CaII H and K, G-band,
MgIb and measure their redshifts. The rest objects have too noisy
spectra.
We make a preliminary classification of all emission-line galaxies similar to that of Salzer ([1989b]). We combined his more detailed types SS, DHIIH, HIIH, all with HII-region type spectrum and of low enough luminosity, into one general type -- BCGs.
We conclude that Case ELGs give the high fraction of BCGs -- about 60 % of all galaxies with strong enough emission lines, and more than 40 % of all Case galaxies, marked with some code of the presence of [OIII] line. Among the ELGs coded with ``vs'', ``s'' and ``m'', BCGs comprise up to 80 %.
The redshift distribution of the detected ELGs shows no undersampling up to z=0.04, and thus these galaxies can be used to study their large-scale spatial distribution up to the distances of 120h-1 Mpc. Concatenation of the Case BCG sample with those from the new Hamburg/SAO survey, bording the Case sample from the North, and with SBS BCG sample, closing the large region of about 3000 square degrees, will open new perspectives for studying the spatial distribution of BCGs, the effects of environment on BCG properties and the problems of dwarf galaxy formation and evolution.