Tertiary deposits are extremely rare in the western part of Tyosen Peninsu-la while occur in scveral isolated areas of very limited extension along the ea-stern coast., The east coast Tertiaries are party of marine and party of terrestrial origin, and there are a number of coal-fields where coal-bearing formations are rich in plant fossils, as in the environs of the town Hoko in Keisyo-hoku-do, Tusen coal-mines in Kogen-do, Tyohori coal mines in Kankyo-nan-do, Kissyu-Meisen district, Ranan, Seikirei, Kainei, Kokangen and Agoti, all in Kankyo-hoku-do; especially the last three fields are situated in the extreme north of the peni-nsula and farther north there is the Konsyun coal-field which already lies in t-he confine of Manchoukuo., Recently the present writer made a large collection of plant fossils in the Tusen formation of the Tusen coal-mines, the Kantindo of Kantindo and Hugando, both in the Kissyu-Meisen district, and the Engelhardtia-bed of Ryuhokudo of the Kokangen coal-mines., The plant fossils from the Kantindo formation is listed on table II and those from the Engelhardtia bed on the table V., The Kantindo flora is believed to be nearly contemporaneous with that of the Tigano-ura plant beds of Siogama and that of Nenosiraisi, both near Sendai; the plant beds of Siogama belong to the Saboyama group., The flora of the Engelhardt-ia bed is somewhat older than the Kantindo flora; both are Miocene in age, none being Palacogene.,
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