  As a pilot survey for the forthcoming 6dF Galaxy Redshift Survey,
spectroscopy of galaxies selected in J (1.2 mu) with the DENIS survey was
performed at the UKST using the FLAIR II multi-object spectroscope. 69 galaxy
redshifts (z's) were obtained in a high |b| field and an additional 12 z's in a
low latitude (b=-17 deg), obscured field. This study illustrates the
feasibility of obtaining z's with optical spectra on galaxies selected at much
longer wavelengths. It validated a very preliminary algorithm for star/galaxy
separation for high |b| DENIS objects, with 99% reliability for J < 13.9.
However, the FLAIR II z determinations required substantially longer
integration times to achieve 90% completeness than expected from previous
optical surveys at comparable depth. This is mainly due to a degradation in
overall fibre throughput due to known problems with ageing of the
prism-cement-fibre interface with exposure to UV light. Our low |b| (high
extinction) field required 2.5 times more exposure time for less than 50% of
successful z measurements. Among the J <= 13.9 galaxies with measured z's, only
37+/-6% display emission lines, in comparison with 60% of emission-line
galaxies (ELGs) in optical samples of comparable depth. The ELGs are, on
average, 0.5 mag bluer in B-J than non-ELGs of the same luminosity. We confirm
a previous optically-based result that the fraction of ELGs increases rapidly
with decreasing galaxy luminosity. The J-band luminosity function is estimated.
Our high latitude field displays a concentration of galaxies at cz ~ 38000 km/s
suggesting a possible supercluster. A radial velocity is reported for a galaxy
lying near the projected centre of the Abell 1434 cluster of galaxies, for
which no cluster z is currently available.
