Chloroplast stroma crystals similar to those reported by PERNER (1962, 1963) but different from those described by other workers were demonstrat ed in Vicia faba chloroplasts. They were absent in chloroplasts isolated in no sucrose, 0.3 M sucrose or in situ material either fixed in the absence of sucrose of fixed in the presence of 0.3 M sucrose. They were present in chloroplasts isolated in 0.5 M sucrose and in situ chloroplasts fixed in the presence of 0.7 M sucrose.