sites. Galinat et al (1956) found definite evidence of teo- 
sinte introgression in the archaeological maize at Rich- 
ards’ Caves and Tonto Cave in Arizona. Their review of 
the literature showed that Tripsacoid cobs also occurred 
in Bat Cave and Tularosa Cave in New Mexico and in 
the Hueco Mountain Caves of western Texas. Prelimi- 
nary studies of archaeological material collected by 
Robert Lister from several caves in Chihuahua in north- 
western Mexico indicate that teosinte introgression has 
occurred in that region also. 
Since teosinte is not known to occur in Tamaulipas at 
the present time, there is a question regarding the origin 
of the teosinte introgression in Late Nal-Tel and Dzit- 
Bacal of La Perra Cave. It is probable that this occurred 
in southern Mexico. Wellhausen et a/ regard Dzit- Bacal 
as a subrace of Olotillo, which is highly Tripsacoid and 
they report that modern Nal-Tel is slightly 'Tripsacoid, 
presumably as a consequence of hybridization with Dzit- 
Bacal. 
An Extreme Form of Early Nal-Tel 
As important as the range of variation in these speci- 
mens, or the average value for any one characteristic, are 
the exceptional cobs. One of these in particular, cob 
127D5, is somewhat different from any maize cob which 
we have previously examined. It is eight-rowed and has 
avery slender rachis which is approximately square in 
cross section. The cupules are compressed, deep, and are 
lined with a profuse covering of stiff hairs. The glumes 
are long, fleshy, and completely glabrous. They have 
the aspect of normal glumes of a wild grass. It is not 
likely that they completely enclosed the kernels, but they 
may have surrounded all parts of the kernels except the 
upper surfaces. The cupules, which in ordinary maize are 
tightly compressed on the rachis, with their lateral wings 
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