The integrated Bragg intensities of the (111) reflections of perfect crystal Ge and Si have been measured with a higher accuracy than heretofore. Ge was measured using x‐ray wavelengths of 0.56 and 1.54 Å, and Si using 1.54 Å. Comparison of the scattering factors so obtained with those measured previously by the same method or by the Pendello¨sung fringe method leads us to the conclusion that there is not a systematic difference between the two methods, as has been suggested. We find that the reflectivity in the wings of the Bragg peak is much lower than the calculated value, and this effect would have to be taken into account if accuracies of the order of 0.1% are envisaged. We also measured Si (222) and found results in agreement with other reflection measurements, but not with recent transmission measurements.