The propagation of a density disturbance in nuclear fluid is considered for the case when the nuclear equation of state is derived from a Skyrme-type effective nucleon-nucleon potential. It is shown that the velocity-dependent terms of this potential are responsible for the possible formation of solitary waves in nuclear matter. These solitons are rarefaction waves and not compressional as previously suggested. Their amplitudes increase with increasing temperature, which makes them a possible mechanism for nuclear multifragmentation.