Upper Cretaceous Foraminifera from Japan 
Kiyoshi Asano 1 
In this paper the discovery in Japan of 
smaller Foraminifera from the Upper Creta- 
ceous strata is recorded for the first time. This 
contribution, in addition to its specific bio- 
stratigraphic application in Japan, has further 
interest by reason of its extension of the geo- 
graphic range of the widely distributed Creta- 
ceous pelagic foraminiferan, Globotruncana. 
In the north Pacific region, Globotruncana 
has heretofore been known only from the 
East Indian archipelago and from California. 
This paper forms part of a project initiated 
by the Natural Resources Section, General 
Headquarters, Supreme Commander for the 
Allied Powers, for the purpose of assembling 
paleontologic data applicable to solution of 
stratigraphic problems connected with explo- 
ration for oil and coal in Japan. In the course 
of the geological survey connected with oil 
exploration in the Cretaceous areas of Hok- 
kaido, Mr. S. Iijima of the Geological Sur- 
vey of Japan collected samples in 1947 from 
the Upper Cretaceous rocks in the vicinity 
of Nakagawa-mura, Nakagawa-gun, Teshio 
district, Hokkaido, which, on examination, 
proved to contain a few specimens of Globo- 
truncana. This identification was confirmed 
by Dr. Paul P. Goudkoff of Los Angeles, Cal- 
ifornia, in a letter dated April 29, 1948. He 
identified Globotruncana canaliculata (Reuss) 
and species of Gyroidina and Pleurostomella 
in the sample. Subsequent study at Tohoku 
University of additional rock samples from 
the Upper Cretaceous of Hokkaido has re- 
vealed that although the occurrence of Globo- 
truncana seems to be rare in the Absehinai 
1 Institute of Geology and Paleontology, Tohoku 
University, Sendai, Japan. Manuscript received 
September 7, 1949. 
area of the Teshio district of Hokkaido, 
Bathysiphon, Glomospira , and Ammodiscoi- 
des are commonly found. 
In a well which was drilled recently to 
test for coal seams at Yokouchi, about 2.5 
km. south of Hisanohama-machi, Futaba-gun, 
Fukushima Prefecture (Lat. 37° 7' N, Long. 
14 1° 00' E), on the island of Honshu, the 
assemblage described in this paper was dis- 
covered in cores from 187 to 215 meters. 
The presence of Upper Cretaceous rocks in 
this general area was already known from 
the work of Tokunaga and Shimizu (1926), 
who recorded Trigonia, Inoceramus, and am- 
monites, indicative of Senonian age. In the 
core samples, from the well at Yokouchi, 
which consist of carbonaceous sandstones and 
shales, Trigonia, Inoceramus, and fragments 
of ammonites were found from 70 to 215 
meters. 
The Foraminifera identified from the cores 
between 187 and 215 meters in the Yokouchi 
well are: 
Silicosigmoilina futabaensis, n.sp. — -dominant 
Globotruncana canaliculata (Reuss) — domi- 
nant 
Globotruncana marginata (Reuss) — rare 
Globotruncana sp. — rare 
Anomalina fukushimaensis, n.sp. — dominant 
Trochammina hisanohamaensis, n.sp. — few 
Robulus lepidus (Reuss) — few 
Robulus futabaensis, n.sp. — rare 
Robulus sp. — few 
Marginulina cretacea Cushman — rare 
Dentalina cf. basiplanata Cushman — rare 
Dentalina sp. — rare 
Vaginulina cf. lata (Cornuel) — rare 
Palmula suturalis (Cushman) — rare 
Ellipsonodosaria sp. — rare 
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