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ART. 2— S. YOSHIWARA: 



It is apparent, that Okinawa-jima is simply a continuation of 

 Öshima, which it closely resembles in tectonics and petrography. The 

 Palaeozoic rocks found in the former are never horizontal, and have 

 the strike parallel to the longer axis of the island, and the dip almost 

 always westward. There is observed no marked folding or faulting 

 on the sea coast, nor in the interior. The principal Palaeozoic rock is 

 clay slate. Greywacke sandstone is also common. Pyroxenite or 

 amphibolite is more extensive, and schaistein less so than in Oshima. 



