492 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 112 



Tanaka Site 



The Tanaka Site is located on the right bank of the Osatsu River, 

 2 miles southwest of its confluence with the Chitose River. The 

 site lies on a small peninsula formed by the juncture of a small, 

 unnamed creek with Osatsu River. Elevation is about 30 feet above 

 sea level, and about 10 feet above the level of the marshland border- 

 ing the two watercourses. The peninsula is level, with gently slop- 

 ing sides. The site is part of the farm of Mr. Sadaiichi Tanaka, 

 whose house and barns cover portions of the occupied area. Mr. 

 Tanaka reports finding sherds and stone tools in his excavations for 

 potato cellars and other deep diggings. He cooperated wholeheart- 

 edly in the plan to excavate on his land and deferred cultivation of 

 the field until our work was completed. For this great kindness, I 

 again express my sincere appreciation. 



Since the site had been covered with volcanic ash during relatively 

 recent times, no artifacts were found on the surface. Four round, 

 shallow depressions represent the locations of semisubterranean pit 

 houses. The visible pits are about 30 feet in diameter, with a maxi- 

 mum depth in the center of about 1 foot. Six additional pits are 

 in a wooded area about 30 yards southwest of the Tanaka homestead. 

 In another wooded area, about 200 yards east of the Tanaka Site, 

 on the south bank of Osatsu River, is another group of 10 housepit 

 depressions in an excellent state of preservation. According to a 

 local informant, Ainu graves containing glass beads, iron swords, and 

 similar articles of recent origin had been found when the area was 

 cleared of trees in about 1920. Since the area has been cultivated 

 repeatedly no evidence of the graves is now visible, and testing 

 yielded no indication of graves. 



A test excavation 5 feet wide by 10 feet long was made in a por- 

 tion of the Tanaka Site not showing a housepit, in order to determine 

 normal soil conditions. This test revealed the layer of volcanic ash 

 on the level surface to be 16 inches thick. Beneath this layer a stra- 

 tum of black soil 20 inches thick was found overlying the brown clay 

 subsoil resulting from the decomposition of earlier volcanic ash 

 deposits. -"* 



Throughout the black stratum were scattered sherds, obsidian 

 chips, and occasional stone tools. The sherds (411627) were identifi- 

 able as representing several cultural periods: (1) Middle Jomon 

 (Yoichi type pottery) ; (2) Later Jomon (Nopporo type) ; and (3) the 

 Epi-Jomon with Ebetsu, Satsumon, and Haji-like wares, whose exact 

 relationships have not yet been defined. Stone implements found 

 are small triangular arrowpoints (411631), a broken celt (411630), 

 and chipped flakes and spalls showing use as scrapers. 



