68 AlîT. 2. — v.. KOTO : 



associated with the preceding at Kui-am^^. 



The series of which the above-mentioned rocks form the 

 constituents, dips southeast, and makes up the terrane as far as 

 Tong-poJx. It is capped by green porphyrite and forms a hill 

 which overlooks the eumnai from the northwest. 



The sudden appearance of this geologically interesting but 

 stratigraphically doubtful complex in the heart of Ch>jöI-Ja-Do is 

 foreign to my experience in Korea. As is clear from the brief 

 description given, the rocks are very much crushed and deformed, 

 owing to the intense shearing during the mountain-building of 

 the Chiei-san Sphenoid. They, therefore, bear the old aspect 

 of crystalline and semi-crystalhne schists. Originally, they were 

 partly spherulitic, partly tuff-porphyroidic, partly sandy clastic 

 rocks ; and in the present state of my knowledge, I am rather 

 pHic disposed to include them in the 3lct amorphic Mesozoic. The 



Mesozoic ^ ^ 



complex greatly resembles the Taunus sericite- schist and gneiss 

 of the Lower Rhine, and in another respect the *' Bündner 

 Schiefer " "^ of eastern Switzerland. 



An allusion has been already made to the same kind of 

 rocks occurring at Pong-nai-jyang '\ Therefore, I may be justified 

 in extending the area of this complex southwards toward Po-söng, 

 and also northwards tow^ard Ok-koa, which I shall presently 

 describe. 



Yabe and Inouye took the north- south route from Tonq-pok 



TONG-POK ^ ^ 



Ok-koa ^^ Oka-koa, as in their trip from Iloa-siin to Tong-pok, though 

 at a different season. For the first six kilometers, a sheared, 

 coarse muscovite-granite made its appearance with plenty of 



^) mm 



'!) See footnote 5, page 49. 



Metamor- 



