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The Ohio Journal of Science [Vol. XVIII, No. 4, 



sexual state of the tissue involved. If we hold to the reasonable 

 hypothesis that the presence of a positive character is due to 

 the presence of a factor or group of factors, then the absence of 

 an awn on the staminate lemma is due to latency caused by 

 the presence of the male condition in the given cells. 



The relative position of the staminate and carpellate flowers 

 in the inflorescence is reversed in various genera from what it 

 is in the wild rice. In the aroids the staminate flowers are 



Fig. 16. Staminate inflorescence of Zea mays L. 

 Fig. 17. Carpellate inflorescence of Zea mays L. 



usually above and the carpellate below. In the gama-grass, 

 Tripsacum dactyloides L., the same is true and the two regions 

 of the inflorescence show a very remarkable dimorphism. The 

 lower part, containing the carpellate spikelets is remarkably 

 modified. The dimorphism exists not only in the flowers and 

 glumes but extends into the stem. The modified carpellate 

 spikelets are enclosed in pockets, formed of highly modified 

 joints of the stem which develops cleavage planes, the joints 

 being separated at maturity, giving rise to very remarkable 

 fruits. 



