314 BUREAU OF AMERICAN ETHNOLOGY [Bull. 177 
Disk.—The coiled central section of the bottom of a Rupununi Plain 
vessel from R-3 appears to have been rounded into a small disk 3.8 cm. 
in diameter. Thickness is 11 mm. at the center and 7 mm. at the edges. 
The exterior surface is flat and the interior convex. 
Shaft polishers (pl. 68, a-~A). —Nineteen sherds of Kanuku and Ru- 
pununi Plain from R-5 and 46 from R-6 have one or more deep, 
straight grooves on the surface. The majority are flat griddle or base 
sherds 1.0 to 1.8 em. thick, but a few are only 8mm. thick. The grooves 
vary in depth from 3 to12 mm. The deepest have weakened the sherd 
so that it has usually broken along the bottom of the groove. Where 
there are two or more grooves on the same surface, they typically run 
ut right angles. Groove width varies from 6 to 14 mm. and is correlated 
with depth suggesting that the narrower and shallower grooves were 
worn by the edge of the shaft while the deep ones encompassed its total 
diameter. A few sherds show the end of a groove, which tapers to a 
rounded tip. One sherd has a groove on both surfaces. A stone with 
similar grooves also came from R-6 (cf. pl. 68,2). 
Rubbing tool—An approximately cubical piece of pottery with 
orange, sandy paste has scratches on one face suggesting use in rubbing 
or abrading. The squared edges look trimmed. The object is 4.5 by 
5.0 cm. and 3.0 em. thick. The absence of coarse sand temper charac- 
teristic of Kanuku Plain and the unusual thickness rule out the possi- 
bility of this being a reused sherd and indicate intentional 
manufacture. 
Bone ARTIFACTS 
Either no consistent use was made of bone tools, or this material has 
not been preserved. Fragments of long bones and antler tips of deer 
from R-22 show no signs of use. Among a number of deer and rodent 
bones from R-20, Cave 4, only one showed such marks. This was a 
long bone that had been split down the middle with a steel knife. Four 
small fragments of turtle carapace were collected from R-20, Cave 3, 
one of which is worn along one edge suggesting use as a scraper, 
OBJECTS OF EUROPEAN ORIGIN 
Eleven sites produced objects of European origin, some of which 
were datable with sufficient precision to permit orientation of the 
ceramic seriation. Materials include glass, earthenware, iron, and tin. 
We are indebted to C., Malcolm Watkins and Edgar M. Howell of 
the Museum of History and Technology, Smithsonian Institution, and 
‘George Metcalf of the Division of Archeology, Smithsonian Institu- 
tion, for the identification and estimated datings, which are) shown 
in table L. 
