  We report measurements of mesoscopic fluctuations of elastic cotunneling in
Coulomb blockaded quantum dots. Unlike resonant tunneling on Coulomb peaks,
cotunneling in the valleys is sensitive to charging effects. We observe a
larger magnetic field scale for the cotunneling (valley) fluctuations compared
to the peaks, as well as an absence of "weak localization" (reduced conductance
at B = 0) in valleys. Cotunneling fluctuations remain correlated over several
valleys while peak conductance correlations decreases quickly.
