8 AKT. l.-S. VOSHIWAKA : 



jiniM and in the Ilu'ya sül)gi'()ü|) and Kei islands are very limited in 

 extent. In Kei-jinia, the old reefs are found in small detached areas 

 only in its western part, the rest of the island being composed of heaps 

 of coral fragments of a very I'ecent origin. 



Far to the east of Okinawa-jima there are three isolated islands, 

 known as South lîorodino (Minami-öagari), Xorth lîorodino (Kita- 

 öagari) and lîasa. Tlie coral reefs seem to cap these islands îind 

 attain in the first a height of 250 ft. above the sea, while in the 

 second and third the highest points are not over 150 ft. The reefs of 

 South Borodino are said to form terraces. Another isolated group of 

 small islands, called the I'innacles, lies far to the north-east of the 

 Yaeyama subgroup. In one of them called Hoa-pin-su (Waheizan) 

 Mr. T. Kuroiwa saw tlie traces of old reefs on the southern, Avestern 

 nnd eastern sides. 



, The Osliivia Group. 



Oshima, with the four large dependent islands, Kikaiga-shima, 

 Tokuno-shima, Okinoerabu-jima, and Yoron-jima, constitutes the 

 Oshima' group, and lies immediately to the north of the Okinawa 

 group. 



In Okinoerabu-jima, the Palaeozoic hills of small extent running 

 from north-east to south-west, are found encircled by the raised reefs 

 forming a large plateau, which attains an elevation of about 200 ft. 

 above the sea, while the older rocks have, at a place called Oyama, an 

 elevation of (587 ft. In the reefs a few terraces are observable near the 

 coast, where they show cliffs 20 to oO ft. in height. Yoron-jima, 

 which I was unable to visit, probably show a distribution of the reefs 

 similar to that in Okinoerabu. 



The foundation of Tokuno-shima is made up of Palaeozoic and 

 pliitonic rocks, which rise to the height of 2,207ft. above the sea. The 



