western Mexico and are found in three other caves — 
Slab, Tau and Olla—in the State of Chihuahua. Non- 
tripsacoid maize resembling a Mexican race, Chapalote, 
was found in the lower levels of Swallow Cave. 
Galinat et al (16) found tripsacoid cobs to be quite 
common among the prehistoric specimens from Richards 
Cave and Tonto Cave in Arizona. Both sites are regarded 
as relatively late. Galinat (unpublished) found also that 
the early maize from Cebollita Cave in New Mexico is 
not tripsacoid, while later maize includes many specimens 
showing teosinte introgression. 
The six studies on archaeological maize reviewed above, 
only one of which was known to Weatherwax and Ran- 
dolph, as well as the data on fossil pollen, support the 
theory that teosinte, because it is a hybrid of Tripsacum 
and cultivated maize, came into existence only after the 
cultivation of maize was well established. 
TAXONOMIC STratus OF TEOSINTE 
When the transfer of the two species of H’uchlaena to 
the genus Zea was published (37), it was made clear, we 
believe, that our previous conclusion as to the origin of 
teosinte did not influence our conviction that the groups 
should be made congeneric—that the transfer was justi- 
fied regardless of the manner of the origin of teosinte or 
corn. Weatherwax (52, 53) and Randolph (381, 32) have 
overlooked or ignored these statements and have repeat- 
edly confused the taxonomic change with the issue of the 
origin of teosinte. If we could agree with their theory 
that corn and teosinte originated by divergent evolution, 
our conviction that the two groups ought to be regarded 
as congeneric would not be weakened in the least. 
Randolph himself (82) recognizes that hybrid inter- 
grades between corn and teosinte do occur naturally and 
describes the intergradation as occurring in the very same 
[ 379 | 
