  We present spectroscopic observations of the stellar motions in the disk of
the superthin edge-on spiral galaxy IC 5249 and re-analyse synthesis
observations of the HI. We find that the HI rotation curve rises initially to
about 90-100 km/s, but contrary to the conclusion of Abe et al. (1999) flattens
well before the edge of the optical disk. Over most part of the optical disk we
have been able to establish that the (tangential) stellar velocity dispersion
is 25-30 km/s. From earlier surface photometry we adopt a value for the radial
scalelength of the disk of 7 +/- 1 kpc, a vertical scaleheight of 0.65 +/- 0.05
kpc and a disk truncation radius of 17 +/- 1 kpc. The very thin appearance of
IC 5249 on the sky is the result of a combination of a low (face-on) surface
brightness, a long scalelength and a a sharp truncation at only about 2.5
scalelengths. From various arguments we derive the stellar velocity dispersions
at a position one radial scalelength as sigma_R about 35 km/s, sigma_{theta}
about 30 km/s and sigma_z about 20 km/s. This is comparable to the values for
the disk of our Galaxy in the solar neighborhood.
