  We study numerically and by scaling arguments the probability P(M)dM that a
given dangling end of the incipient percolation cluster has a mass between M
and M + dM. We find by scaling arguments that P(M) decays with a power law,
P(M)~M^(-(1+k)), with an exponent k=dBf/df, where df and dBf are the fractal
dimensions of the cluster and its backbone, respectively. Our numerical results
yield k=0.83 in d=2 and k=0.74 in d=3 in very good agreement with theory.
