Up to the present, there is no report on the iron-concretions in the soil of North Manchuria. On my journey in North Manchuria in 1933, I found the iron-concretions widely distributed in the black soil on the terrace of diluvial formation. The form of concretions is usually globular varying in the diameter between 2 mm. and 7 mm. Its surface is dark brown and generally smooth, but some has the semi-metallic lusture. It contains much more manganese than that of South Manchuria which had been reported by other investigators. The results of the total analysis of the iron-con c retions collected in North Manchurian soil are as follows: (snip)