On Hosokawa's Line and the Response

Abstract

T. HOSOKAWA (1934, 1935) advocated, as a result of his explorations which were carried out in the Marianne Islands in 1933 and 1944, that there be recognized a strikingly deep floristic discontinuity of plant distribution between the Mariannes and the Bonins including the Volcano Islands, the former of which is conceived to be a part of the northernmost border of the floristic region of Papualand and the latter to be that of the southernmost border of the Asiatic temperate floristic region, both in the western Pacific. He therefore marked it on a map with a line of demarcation between them (HOSOKAWA 1934-a, -b, 1935), which was designated by the name of HOSOKAWA's line in KANEHIRA's paper (1935-b).