Abstract
The thirty eight successive years' statistics of rice production per unit area (=tan) in each of the eleven counties of Hokkaido Prefecture were analysed applying the definition of bad harvest as given formerly by the author being taken into account. From the chronological data. On rice yield during thirty eight years at those eleven counties, it was concluded that "Oshima" County belongs to the north-east type, "Hiyama" and Shiribeshi" to the intermediate type and other eights to the north type in regard to bad harvest (fig. 8). It was observed that the north type consisted of four regional linkage groups : I-IV, between the trans-mode percent and the estimated rice production (koku/tan) for 1950 (fig. 9), and these groups laid in a wavy arrangement from north-east, Okhotsk Sea Coast of "Abashiri" County to south west (fig. 10). Therefore, the bad harvest of Hokkaido prefecture might cames from the Okhotsk Sea.
