The scaling relations between some global properties of ellipticals (Es), known as the "Fundamental Plane'' (FP; Dressler et al. 1987; Djorgovski & Davis 1987), is clearly a manifestation of a great "regularity'' in the properties of Es. Although a proof of its "universality'' is still lacking, the FP has been widely applied to various problems: from the study of peculiar motions (Lynden-Bell et al. 1988; Jørgensen et al. 1996), to the study of the evolution of M/L ratios (van Dokkum & Franx 1996; Kelson et al. 1997), and measurements of q0 (Bender et al. 1998).
The "regularity'' of the E's properties, shown by the FP, must be connected to their gross structural characteristics and to their formation and evolutionary mechanisms (Djorgovski et al. 1995 and references therein). To understand this connection is however a very hard task, especially in view of the problems posed by the "thinness'' of the FP itself (Ciotti et al. 1996). Apart from the obvious similarities, it is a matter of fact that Es do not constitute a homogeneous family of galaxies: Es not only have substantially different photometric and kinematical properties, but they also host a variety of sub-components, like inner disks, counter-rotating cores, outer rings, dust lanes, etc. (Illingworth 1983; Kormendy & Djorgovski 1989; Caon et al. 1993; Michard & Marchal 1994; Capaccioli & Longo 1994; Scorza & Bender 1996; Graham et al. 1996; Graham & Colless 1997; Busarello et al. 1997; Prugniel & Simien 1997; Carollo et al. 1997, and references therein).
The possibility that many Es have disks that escape photometric detection (Simien & de Vaucouleurs 1986; Capaccioli 1987; Rix & White 1990; Saglia et al. 1997), and the dichotomy between the two families of boxy and disky Es lead to the possibility of a new classification scheme, in which galaxies formerly belonging to the same Hubble type are separated according to isophotal shape, and in which a continuous sequence exists between Es and S0s (Kormendy & Bender 1996). Since the above scenario is manifestly at odds with the "regularity'' of the FP, the question arises to what extent the "global'' quantities entering into the construction of the FP are representative of the real status of the galaxies.
In this respect, an important question is whether the central
velocity dispersion 
is fully representative of the dynamical
status of a galaxy. There is much evidence that this is not the case:
due to differences in velocity dispersion profiles and anisotropy,
masses derived from can be wrong by a factor of ten
(Tonry 1983; Richstone & Tremaine 1986;
Mathews 1988); in presence
of central, kinematically distinct sub-components, the value of
is likely to be more connected to the sub-component than to
the galaxy as a whole; Es are dynamically non-homologous systems: the
slope of the velocity dispersion profile is correlated to in
such a way that there is a systematic departure of the kinetic energy
from a simple scaling of (Graham & Colless 1997;
Busarello
et al. 1997); finally, the rotation, although not dominant in Es, plays a
non-negligible role (Busarello et al. 1992;
Prugniel & Simien 1994, 1996; Busarello et al. 1997;
D'Onofrio et al. 1997).
To fully understand the complex kinematics of Es, and to analyze the connection between the individual properties of Es and the scaling laws, it is essential to have access to kinematical data as accurate, extended and homogeneous as possible. One of the objectives of the present work is to obtain homogeneous sets of data for magnitude-limited samples of elliptical galaxies belonging to different clusters.
In the present paper we present new stellar kinematical data for 13 galaxies in the Fornax cluster.
Section 2 describes the observations and the data reduction. In Sect. 3, we give a short description of the major features of each of the kinematical profiles. Section 4 provides a comparison of our data with previous observations, and in Sect. 5 we briefly summarize our findings. The data themselves are presented in Appendix A and in Table 3 (available in electronic form from the CDS).
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