Measurements of ionic conductance and electron lifetimes have been made on the grains of two AgBr photographic emulsions, one composed of regular octahedral grains bounded by (111) planes and the other composed of regular cubical grains having (100) faces. The field decays more slowly in the cubical grains, indicating that crystal habit affects ionic conductivity. Electron lifetimes were observed to be approximately equal to the field decay in the octahedral grains and shorter than the field decay in the cubical grains, in contrast to the tabular grains measured previously, in which the electron lifetime was longer than the field‐decay time. An explanation for this is proposed, based on the assumption that the interstitial silver ions are inhomogeneously distributed in the volume of the grains.