Prare LXXVI. Evidence of teosinte introgression and 
maize <teosinte hybridization. A. The cob to the far 
left is a typical maize ear and shows evidence of intro- 
gression of tripsacoid segments associated with chromo- 
some 9, and possibly chromosome 4+. The cobs to the 
right are arranged in a series of increasingly pronounced 
tripsacoid characteristics. The extreme is the cob to the 
far right with its massive lower glumes and deep cu- 
pules. This cob, which was part of the maize harvest, 
is comparable in morphology to a maize backcross to the 
maize » teosinte hybrid. 7/10 actual size. B. This Fi 
maize < teosinte hybrid came from the same field as the 
cobsin A. Note the two-ranked rachis, the paired spike- 
lets, and the kernels forcing open the enclosing lower 
glumes; all typical characteristics of the Fi hybrid. 7/10 
actual size. 
[ 803 ] 
