  From the observations reported to VSNET, we detected short fading episodes in
two dwarf novae, RX And (orbital period 5.0 hr) and SU UMa (orbital period 1.8
hr). The episodes in RX And can be naturally explained as the response to a
short-term reduction of the mass-transfer rate. A qualitative comparison with
VY Scl-type fadings is also discussed. In SU UMa, the same explanation is
expected to be more difficult to apply. The viable, but still poorly
understood, possibilities include the temporary reduction of quiescent disk
viscosity and the temporary reduction of mass-transfer rate. If the latter
possibility is confirmed, we probably need a different mechanism from that of
VY Scl-type stars.
