162 ART. 2. — B. KOTÔ: 



that here the members are entirely of sedimentary origin, but 

 wanting in limestone. 



The above-mentioned four belts of sericitic and pliyllitic 

 rocks, usually included in the epi-zone of crystalline schists, 

 have their petrographical features so much alike that handspeci- 

 mens cannot be distinguished from one another, and on this 

 ground I may be justified in giving them the common designa- 

 tion of the Phyllite Series. As to the age of the series nothing 

 definite can be said. In the present state of my know- 

 ledge, I shall assign it provisionally to a metamorphic 

 Mesozoic, although it is not intended thereby to exclude 

 the idea of its being of the Proterozoic (Algonkian), or 

 even of the Palaeozoic formation. 



IV. The Great Granitoid Series 



Korea is a land of granite and gneiss. In Gottsche's geolo- 

 gic map of 188G, the whole area was colored in one tint repre- 

 senting granitic rocks with only a few patches of later igneous 

 and sedimentary formations. The map of Messrs. Nishiwada and 

 IsHii became slightly polychromatic, and in my manuscript map 

 of 1902, some more legends were added. Even in recent maps 

 more than lialf of the peninsula is colored to show granitoid 

 rocks. 



At the close of the preceding Phyllite period, Korea under- 

 went a complete change. A grand intrusion of granite took 

 place throughout the peninsula, shattering the crust into diverse 

 patches and metamorphosing the sediments and ancient lava -flows 

 and dykes into schistose and foliated rocks. The intrusion and 



