Oscillation phase dynamics  in  the  homogeneous  autooscillating
Belousov-Zhabotinsky  (BZ)  reaction  has  been  studied  by  computer
simulations.  The  wave   dynamics   in   autooscillating   media   is
qualitatively different from those in excitable media for sufficiently
long waves. We propose a classification of  chemical  waves  which  is
based on the analysis of shape of the dispersion curve. This  delimits
conventionally  the  waves  with  properties  analogous  to  those  in
excitable media - "trigger waves", from "phase waves".