JOURNAL OP THE COLLEGE OF SCIENCE, TOKYO IMPERIAL UNIVERSITY. 



VOL. XXXIX., ARTICLE 6. 



Fossils from the Miura Peninsula and its 

 Immediate North. 



By 



Matajiro YOKOYAMA, Rigakuhakushi. 



Professor of Palaeontology, Imperial University of Tokyo. 



With 19 Plates and 1 Map. 



Introduction. 



The peninsula of Miura which bounds the Uraga Strait, the 

 entrance to Tokyo Bay, on the west and is a little over 20 

 kilometres from north to south and 4 to 12 kilometres from east 

 to west is, geographically speaking, a low hilly country rarely 

 attaining a height over 200 metres above the level of the sea. 1} 



This hill} 7 country gradually diminishes in height towards the 

 north, and not far south of Yokohama, passes into the great plain 

 of Tokyo, the most extensive and also one of the most populous 

 in the whole empire, but which, until some five centuries ago, 

 was in greater part a wilderness known under the name of 

 Musashino'^ and with but a sparse population. 



Geologically, the hilly peninsula as well as the plain is made 

 up of very young formations which are in part undoubtedly 

 Pliocene and in part either Pliocene or Pleistocene. 



1) There are only three peaks which are over 200 ru. in height. They are Ôgusuyaina 

 (242 ni.), Futagoyaina (228 m.) and Hatakeyama (208 in.). 



2) From Husashi, the name of the province in which the plain is situated, and No, a 

 grass-grown, uncultivated field. 



