was possible in this case, be distinguished from individual 
grains of teosinte, populations of pollen grains can usually be 
distinguished. A comparison of the frequency distributions of 
200 archaeological grains of pollen from the Bat Cave site in 
New Mexico with 200 grains of pollen from a teosinte growing 
in the Valley of Mexico shows some overlapping (/9). In the 
region of overlap the grains of corn and teosinte cannot be 
distinguished. But 59 percent of the Bat Cave pollen grains are 
larger than the largest teosinte grains. Distinguishing these 
from the teosinte grains is no problem. 
The population of the fossil pollen grains from the Bellas 
Artes site is clearly different from any population of teosinte 
grains with which it has been compared. There are, as Kurtz e7 
al. have stated, at least five pollen grains, 36 percent of the 
total, too large to be identified as teosinte pollen. 
The teosinte theorists now argue that the fossil pollen grains, 
earlier considered to be too small to be reliably distinguished 
from teosinte grains, are too large to be those of a primitive 
corn (/, 5). This argument is based on a correlation showing a 
relationship between length of ear and pollen size (20). The 
length of the ear determines to a considerable extent the length 
of the styles, commonly called *‘silks’’, that the pollen tubes 
must travel to reach the ovules and effect fertilization. 
Since the ears of a primitive wild corn are assumed to have 
been small, the earliest intact cobs from San Marcos Cave in 
the Tehuacan Valley vary in length from 19 - 25 mm (/4), it Is 
concluded that the pollen of such a corn must have been corre- 
spondingly small. This does not necessarily follow. Actually 
the correlation mentioned above, although statistically signifi- 
cant, is strongly influenced by two races, Jala and Huesillo, 
that have unusually long ears and unusually large pollen. The 
correlation among the remaining eight races included in the 
study is by no means so strong and there are notable excep- 
tions. The highly evolved Mexican race Vandeno, for example, 
has pollen grains of about the same size, 83.9 microns, as those 
of the primitive Mexican popcorn race Nal-Tel, 81.2 microns, 
although its ears are more than twice as long as Nal-Tel, 17.2 
and 7.9 cm, respectively. 
243 
