One more important and clear-cut conclusion can be 
drawn from the evidence furnished by the prehistoric 
husks. Had maize originated from teosinte, as some bot- 
anists still suppose, then the early primitive races of maize, 
only slightly removed from teosinte in their characteris- 
tics, might be expected to possess short husks scarcely 
covering the ears. The early evolution of the husks would 
then have become a matter of a progressive increase in 
length to enable the husks to enclose progressively longer 
ears. In the Bat Cave material the evolutionary sequence 
in the husks is exactly the reverse of this. The earliest 
husks are the longest. Indeed, they are several times 
longer than the longest ear in the same stratum. The 
early evolution of husks has been a matter of their be- 
coming shorter and wider rather than longer. 
Thus, the accumulated circumstantial evidence against 
the hypothesis that maize originated from teosinte is 
finally reinforced by direct evidence which is almost 
conclusive. 
LEAF SHEATHS 
In addition to the husks which are largely modified 
leaf sheaths, ten specimens of true leaf sheaths were 
found—one from Stratum IV, the remaining nine from 
VI. The specimen from Stratum IV is completely gla- 
brous; of the nine specimens from VI, four are com- 
pletely glabrous on both inner and outer surfaces, three 
have hairs and prickles on both surfaces, one is glabrous 
on the outer surface and beset with numerous short hairs 
on the inner, and one bears short hairs on the outer sur- 
face but is glabrous on the inner. 
The significance of these variations is not yet clear. 
Only one fact is certain. At least part of the maize found 
in Bat Cave possessed glabrous leaf sheaths. ‘True gla- 
brousness is not common in maize varieties today, except 
[ 235 ] 
