The Royal Astronomical Society. All Rights Reserved. These galaxies are intermediate between ellipticals and lenticulars, and they both have a small nuclear stellar disc in addition to their main outer disc.
Colour images reveal no colour differences between the nuclear discs and the bulges.
For NGC 4342 this is consistent with the values of the line strengths in the central region derived from the FOS spectra. Both galaxies are rapidly rotating, and they both have velocity dispersions that increase strongly towards the centre. Measurements of V and sigma yield the stellar kinematics at four times higher spatial resolution than available from the WHT spectra. The rapid stellar motions seen in the centre of NGC 4342 suggest a large central mass concentration, possibly a massive black hole. The stellar kinematical measurements for both galaxies will be interpreted quantitatively with detailed dynamical models in a series of companion papers.