ents’ has been pretty thoroughly demolished (82, 45). 
Since some varieties of teosinte have obviously been 
modified by admixture with maize, it is almost inevita- 
ble that some varieties of maize have likewise been mod- 
ified by admixture with teosinte. Weatherwax concedes 
this in the same chapter in which Randolph attempts to 
deny it. And if this conflict of opinions proves to be 
confusing to some readers, it at least demonstrates an 
admirable independence of mind on the part of the two 
joint authors. 
Wellhausen ef al (53), in an important paper which 
both Weatherwax and Randolph have repeatedly over- 
looked, report the results of an intensive study, over a 
period of seven years, of more than 2000 collections of 
maize from all parts of Mexico. Of the 25 races of maize 
which they describe, they recognize teosinte introgres- 
sion in 22, primarily on the basis of the induration of the 
rachis and the lower glumes of the ears. Their scores for 
teosinte introgression proved to be strongly correlated 
with chromosome knob number; and more recently, they 
have shown a remarkable correlation with resistance to a 
virus disease, corn ‘‘stunt’’ (7). Here may be another 
case, similar to that reported by Venkatraman and 
Thomas (57), of one of the lower forms of life being 
more perceptive than botanists in recognizing the true 
nature of populations. 
Randolph’s conclusion that there is no cytological evi- 
dence of the introgression of teosinte into maize 1s cor- 
rect only if his assumption that the chromosome knobs 
of maize are not derived from teosinte is valid. But apart 
from chromosome knobs, what cytological evidence of 
introgression could there be? Randolph has repeatedly 
emphasized the remarkable similarity, except for the 
knobs, between maize and teosinte chromosomes. If they 
are indeed as similar as he regards them to be, then even 
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