  We present the sample of gamma-ray bursts detected with the anti-coincidence
shield ACS of the spectrometer SPI on-board INTEGRAL for the first 26.5 months
of mission operation (up to Jan 2005). SPI-ACS works as a nearly
omnidirectional gamma-ray burst detector above ~80 keV but lacks spatial and
spectral information. In this catalogue, the properties derived from the 50 ms
light curves (e.g., T90, Cmax, Cint, variability, V/Vmax) are given for each
candidate burst in the sample. A strong excess of very short events with
durations <0.25 s is found. This population is shown to be significantly
different from the short- and long-duration burst sample by means of the
intensity distribution and V/Vmax test and is certainly connected with cosmic
ray hits in the detector. A rate of 0.3 true gamma-ray bursts per day is
observed.
