SIGNIFICANCE OF THE LARGE POLLEN 
It is the large pollen of the primitive popcorn that seems to us 
to be especially significant and to require explanation. The 
length of the mature ear is only one factor in determining the 
length of the styles that the pollen tubes must travel to reach the 
ovules. Equally important is the extent to which the husks 
protrude beyond the tips of the ears which they enclose. The 
senior author has frequently been impressed by the fact that 
among the early archaeological remains the husks are consid- 
erably longer, on the average, than the longest cobs of the 
same level. This first came to attention in the archaeological 
remains turned up in the first Bat Cave expedition. The only 
husk found in the lower levels of the cave is quite long, 24.5cm, 
more than twice the length of the longest intact cob, 10.3 cm. 
The authors (2/) concluded that the husk must have been an 
involucre of leaf sheaths subtending and surrounding the base 
of an ear but not tightly enclosing it. 
The real nature of this long husk became apparent with a 
study of the specimens from the second Bat Cave expedition 
(22). These led to the conclusion that the long husk found in the 
first expedition may have enclosed, not a single ear, but a pair 
of ears, upper and lower, each with its own shorter husk system 
(Fig. 2). If the silks of the lower ear became exposed to pollina- 
tion only when they reached the terminus of the outer husk 
system they would have been about 23 cm long. This is longer 
than any of the ears in the correlation study reported above 
except the giant ears of the races Jala and Huesillo, but is about 
the length of the longest silks of the race Vandeno. when 
allowance is made for the husks extending several inches be- 
yond the tip of the ear as they do in most varieties. Thus the fact 
that the highly-evolved race Vandeno has the same pollen size 
as the primitive popcorn race, Nal-Tel becomes explicable. 
The two-eared husk system may also explain the two- 
ranked, four-rowed cob found in the lower level of San Marcos 
cave. The teosinte advocates regard this as evidence of the 
evolution of the early Tehuacan corn from teosinte. A more 
simple and obvious explanation is that this cob represents a 
lower secondary ear in a two-eared husk system. Lower sec- 
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