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THE AMERICAN NATURALIST [Vol. LIII 



produces one ^rraiii; but in Country Gentleman sweet corn, a 

 second flower, ordinarily aborted, becomes functional, and the 

 spikelet produces two f?rains. Since there is little or no com- 

 pensation for this in the length of the cob, and insufficient differ- 

 ence in the size and shape of the grain, the ear is producing a 

 larger volume of embryo and endosperm than is ordinarily pro- 

 duced in the same space. As a result of this crowded condition, 

 the straight rows are more or less obliterated for a more econom- 

 ical arrangement. At times, however, a set of conditions, pre- 

 sumably environmental, may limit the size of the grain or 

 increase the length of the cob sufficiently that the rows are almost 



definite expression of a definite characteristic. If the heredity of 

 the two-flowered conditicm of the spikelet had been tested, a more 

 direct explanation would probably have been afforded. 



of hermaphrodite flowers upon the basis that ''the immature sex 

 organs, so-called, of maize seem endowed with the power of be- 

 coming either stamens or carpels." In so far as actual genetic 

 results are concerned, this is, in most cases, at least, a sound 

 working basis, but it is far from exact morphologically. There 

 is no organ in the young maize flower that has the possibility of 

 becoming in some cases a stamen and in others a pistil. The 

 young flower has the ability to become either staminate or pistil- 

 late because it contains primordia of both stamens and a pistil, 

 one or the other of which usually does not develop to maturity.^ 

 Blaringhem's extensive experiments,' in which he attempts to 

 initiate mutation by means of injuries to the plant, fail to take 

 into full account certain very significant facts of morphology. 

 It is probably for this reason that he believes that the acquisition 

 of hermaphrodite flowers in the maize plant is a progressive step. 

 On the contrary, every indication points to the fact that the 

 rudimentary stamens and pistils that have been found in the 

 riowers of maize are the vestiges of organs that have been, and 

 iHit tlie pliylogeiietic forerunners of organs that are to be. 

 Mni-cover, normal behavior shows that in mutilating the plants 

 h.' had merely promoted tlu- production of suckers, which nor- 



of phvsiology (,f mono.vism; but. the nonual plant being under- 

 •f I bid., pp. ]21>-134. 



