Since my first ascent of Tugitaka in July, 1926, the summit was gained 'by climbing parties under my lead in 1928, 1929, and 1930. In these climbs I noticed on the northern face of the top a very distinct cirque^*, unmistakable evidence that the summit of Tugitaka had once borne glaciers.
In 1933, thanks to the gracious support of Prince N. Takatukasa, I was able to organize an expedition party, and make investigations for nearly two months (early October till late November) in the mountain range, the main object being to collect zoological specimens as well as to study the altitudinal distribution of animal life, although other observations, such as those concerning glacial topography, were also made during the expedition. This paper is concerned with the last-mentioned subject. Before doing so, however, a general description of the mountain range will be given.
The Tugitaka mountains, situated in the northern part of Formosa between 24° 10' and 24° 30' N. lat. and 121° 0' and 121° 20' E. long., extend in a NE-SW direction for a distance of nearly 40 kilometers. Tugitaka, which is the highest summit of the mountain ridge and the second highest peak in Japan and her territories, and which is also called Mt. Sylvia by some .authors, attains a height of 3931m (12972 ft. ).
The mountains are composed entirely of Tertiary sedimentaries, showing alternations of sandstone and shale. They can be orographically divided into two parallel chains, the Taihasen-Tugitaka chain, and Daisetu chain, the two being connected by a small ridge on the western side off the Tugitaka main peak. The main ridge, which was the one most thoroughly investigated by the expedition, is represented by the former chain, on whose ridge lie many prominent peaks over 3500m in altitude, such as (enumerated from north to south) Taihasen (3573m), Pasarayum (3500m), Takusyawan (3500m), Potinsiron (3567m), Momoyama (3390m), Yuntaga (3712m), Taraku-ssya (3800m), Tugitaka (3931m), and Battowanômin (3614m). The three principal rivers, Daiankei, Giran-dakusuikei, and Daikôkei, have their sources in the mountains. On the western and northern slopes flow the first two rivers, while the southern and eastern slopes are drained by the last-named, all with deeply incised valleys, along the course of which many steps of terraces, indicating great uplifts of the mountains in recent times, are clearly visible up to considerable heights.
The outstanding features in the topogrphy of the mountains are the flat. topped ridge at high levels, the best examples of which are found on the long ridge stretching from Tugitaka to Taihasen and on the ridges near Daisetu and Battowanômin. These flat surfaces, which are erosion levels that truncate the steeply inclined strata of sandstone and shale, may well be regarded as peneplain remnants. The mountain sides ordinarily have very steep slopes, on which however a number of flat surfaces are easily traceable, some of which may be attributed to erosion levels that were formed in the course of successive uplifts of the mountains, and the rest to fault benches.
The first snow of the year usually falls about the end of October, the glittering snow-capped summit being visible till the end of April from far down the western coastal plain, but, even in January, after a succession of fine days, the snow soon melt away owing to the strong insolation of the tropical sun. Around the mountains live the Taiyal tribe, the well known head-hunting people of Formosa, from which tribe the highest peak has., received the name, Babôhagai.
The intense weathering, so common in the high mountains of the tropics, . is now doing its work in the higher parts of the mountains, destroying the cirque walls and Roches moutonnées or burying the cirque floors under talus-deposits. Glacial topography, nevertheless abounds, thus implying that glaciation at one time was by no means small in extent.

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