Dating of the Remains 
One of the most important questions to be answered 
is the date of the remains. The radiocarbon determina- 
tions (Libby, 1951; Arnold and Libby, 1950) of samples 
of charcoal and other materials from the several levels 
are set forthin Table I. The data from the two excava- 
tions are fairly consistent for the three uppermost levels 
but differ widely for the two lower levels. There is reason 
to believe that the date of 5605 for the charcoal in the 
48-60” level is not valid for the associated earliest maize. 
Tas_e I. Radiocarbon dates of charcoal, wood fragments, and cobs 
from the two Bat Cave excavations. 
1948 Excavations 1950 Exeavations 
Material Level Date Material Level Date 
cobs 0-12” |1752+250 
wood 12-24" | 1907+250] Charcoal 11-15” | 1610+200 
wood 24-36" | 2239+ 250 ” 24-86" | 2816+ 200 
cobs, wood | 36-48/" | 2249+250 “ 36-48” | 20484170 
wood 48-60” | 2862+250 “ 48-60” | 56054290 
Peres ies 60-66" | 3000-3500 = 60-66” | 593814310 
ation 
On the basis of the characteristics of the cobs, especially 
those which represent evidence of teosinte contamina- 
tion, we have concluded that the maize from the 48-60” 
level of Bat Cave is later than the maize of the Abejas 
phase in the Tehuacan caves and earlier than that of the 
Ajalpan phase. This would date it at between 2300 and 
1500 B.C. A similar correlation with the remains of 
maize in Romero’s Cave, Tamaulipas, Mexico, excavated 
by Dr. Richard S. MacNeish (in press) makes it con- 
temporary with the Guerrero phase dated by radiocarbon 
at 1800-1400 B.C. These correlations suggest that the 
earliest Bat Cave maize is probably not earlier than 
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