  We report on time-series photometric observations in the earliest stages of
superoutbursts of the extreme dwarf novae, AL Com and WZ Sge, which started on
2001 May after the 6 years quiescence and on 2001 July after the 23 years
quiescence, respectively. We detected growth of ``early superhumps'' during the
each rising stage. Our observations reject the mass transfer instability for
the trigger of the superoutburst of WZ Sge stars, and show the existence of
some relations between the ``early superhumps'' and the spiral structure, which
give a hint of the origin of the ``early superhumps.''
