Fossils from the Miura Peninsula and its Immediate North. 5 



the Pliocene formation or the Pleistocene formation, as has often 

 hitherto been done, but by some name which has no relation to 

 it. On this account, I here propose the name of musashino 

 Formation for the whole marine series. Then its upper part will 

 be the Upper Musashino and its lower part the Lower Musashino. 

 The fossils described below are those of the latter. 



General Remarks on the Mollusca of the 

 Lower Musashino. 



The fossils which form the subject of the present paper, 

 though partly collected by Dr. Tokunaga and myself, were to a 

 greater part brought together by the late Gordon Yamakawa 1} who 

 showed great zeal in the study of palaeontology, but who un- 

 fortunately died in 1910, while still a student in the university of 

 Tokyo. 



The localities in which the fossils were found are twenty- 

 eight in number. These I provisionally group into six zones 

 which, beginning from above, are as follows: 



1. Naganuma Zone. — Comprising four localities: Naganuma, 

 Sugita, Iijima and Kikkösan. 



2. Koshiba Zone. — Comprising two localities: Koshiba and 

 Of un a. 



3. Kanazawa Zone. — Comprising three localities: Kanazawa, 

 Teramae and Nojima. 



4. Kamahura Zone. — Comprising four localities: Kamakura, 

 Kewaizaka, Uragô and a place between Uragô and Enokido. 



5. Yohosulca Zone. — Comprising three localities: Yokosuka, 

 Otsu and a place between Shioiri and Sakamoto. 



G. Ml.i/ata Zone. — Comprising, besides Motowada and Nagai, 

 five localities (Muköbatake, Iwaiguchi, Jinya-ato, Matsubara-no- 



1) Several, though short, papers were written by this lamented youth on the fossils of 

 the Upper Musashino. They appeared in the Journal of the Geological Society of Tokyo, the 

 most important being those on Opisthobranchiata and on Pteropoda. 



