E d 
ee ARCHEOLOGY IN BRITISH GUIANA 13 
District, B=Berbice Province, E=upper Essequibo River, R=Ru- 
pununi District), and the number to the particular site in question. 
In two cases where the correlation is unquestionable, phases were 
given the names of the actual tribe to which they correspond. Other- 
wise a local geographical term was chosen. Pottery types were 
named according to the binomial system, coupling a proper noun of 
the region with a descriptive adjective. Color terms, such as red 
or white, in the name of a pottery type indicate the use of a slip; 
unslipped surfaces of whatever color are referred to as “plain.” In 
the figures illustrating vessel shapes and rim profiles, solid, blacked-in 
rims are used for plain wares and outlined ones for decorated types. 
Where the data were sufficient, we have tried to apply and to test the 
formula for calculating site duration from rate of sherd accumula- 
tion that we first proposed in an earlier monograph (Meggers and 
Evans, 1957, pp. 245-257). We have brought this method up again 
not because we are convinced of its validity, but because we feel that 
it cannot be either accepted or rejected without further testing, and 
that if we do not make the effort to apply it we cannot expect others 
to do so. 
Finally, an explanation of the system of measurements should be 
made. Because the metric system is easier to use and is the accepted 
system in Latin American countries, we measured all distances and 
altitudes in meters and kilometers and all specimens in centimeters 
and millimeters. However, British Guiana being a British colony, 
all the published geographical descriptions and current linear meas- 
urements are in miles, feet, and inches. As a compromise, geograph- 
ical references were quoted in both systems, while our own measure- 
ments and observations are given only in the metric system. Spell- 
ing of geographical names follows British Guiana usage except in 
the case of the sites of the Taruma and Wai Wai Phases. ‘These 
words are unwritten and no attempt has been made to provide an 
exact phonetic equivalent. 
