On account of the lack of precise knowledge of foreign fruits and the absence of close touch with them, our fruit industry receives very little advantage from those plants of foreign origin. This situation strongly suggests that our list of fruit in cultivation should be revised. Considering the existence of vast range of the climatologieally different areas within our territories, the good selection of foriegn fruits, if logically undertakes, will bring the most valuable contribution toward the fruit industry of this country. It is there fore necessary to gather informations of all known fruit trees of any economic value, with special refference to their native homes, distribution, climatological and edaphic requirment and so on. From the result of an extensive survey conducted with good reference materials at hand, a bulky list of fruit trees of the world was compiled, from which a few representative species were explained here in this abstract paper. Table 1 gives the complete list of 294 species chosen as the material of investigations, and their occurrence in each section of the world was tabulated. It is found from this table that only 87 species are found in the Japanese territories, among which 8 being native to the islands. If 93 are selected as the most important foreign races, 45 comes t o our region under actual cultivation. There are 207 species hitherto uncultivated in this region, among which 30 are consiered the most significant. These are rearranged in Table 6, refferring to the possible adaptability to the various climatic zones of the Japanese territories, which consist of 14 sections classed by the amount of annual precipitation and monthly temperature of January and July. In applying this classification of the Japanese zones to the foreign, the characteristics of the Japanese climatic requirement is most clearly seen, and it shows that the eastern United States and southeastern Asia are only foreign regions which present a striking similarlity to the Japanese territories. This suggests the desirability of introducing fruit trees of these foreign regions into the Japanese area with high possibility of establishing new industries. Central American fruit trees also need to be tested here from the same reason. In investigating the fruit list of these regions, several species of particular interest are enumerated, among which avocados, breadfruit, cherimoya, passifloras, sapotaceous fruit, pecan, black walnut, several species of plums, Ribes, Rubus and Vacciniums are called special attention.
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