June, 1923] 
GERICKE — GENETIC CHARACTERS OF WHEAT 
2 77 
tap water from that which prevailed on plants grown in soils was the appear¬ 
ance of awns on a so-called awnless variety (Sonora). Seven plants out of 
the one hundred produced heads having awns one and one half to two inches 
long, whereas none of the plants grown in soils produced awned spikelets, 
other than the rudimentary organs two eighths to three eighths inch long 
common to that variety. Tap water, and perhaps also the effect of the 
then prevailing climatic complex, therefore served as a means to permit 
expression of a character in wheat that did not appear under the usual 
conditions in which this variety is grown. 
As a much fuller account of the subject matter will appear in due time 
elsewhere, only a short table of data (table 1) is given herewith. 
University of California 
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