April I, 1920 



A Teosinte-Maize Hybrid 



13 



of Tom Thumb where two of these character's were recorded. Thus 

 there is evidence of coherence between height and the character of the 



tassel. 



Disherence with male secondaries is indicated by a correlation of 

 - 0.28 ± 0.07. The negative correlation of - 0.46 ± 0.06 with nodes silking 

 index would also seem a clear example of dis- 

 herence. 



The correlation of 0.47 with days to pollen 

 indicates coherence of this character with height. 

 In both parent populations this correlation was 

 negative, but under most circumstances the late 

 plants of a maize variety are taller than the 

 early plants. 



The negative correlation of —0.33 with length 

 of intemode on third is in the direction of a dis- 

 herence, though this is probably associated with 

 the negative correlation between height and 

 sucker index, which is to some extent physical. 

 Anything which tended to interfere with the 

 growth of the main culm would doubtless stimu- 

 late the development of all the branches. 



TOTAt, LEAVES 



The total number of leaves on the main culm 

 in Tom Thumb is usually 1 1 , in Florida teosinte 

 about 37. The mean in the Fj hybrid plants was 23, with a range 

 from 9 to z^. The distribution (fig. 2) is normal, and the variability 



as measured by the coefii- 

 cient of variation is the low- 

 est recorded for any char- 

 acter. 



The larger varieties of 

 maize equal or exceed teo- 

 sinte in number of leaves 

 just as they do in height. 

 In both maize and teosinte 

 total number of leaves is a 

 character very little affected 



30r 





/fS/GAfT //VO£C/M£TePS 



Fig. I.— Height: frequency dis- 

 tribution of plants in Fj. Class 

 value, 2 dan. 



20 



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Q 



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Fig. a.-Total leaves: frequency distribution of plants in F2. by changes in the environ- 



ciass value, one leaf. ment. In maize there is 



usually an intra-varietal correlation of about 0.3 between total leaves 

 and height. Corresponding data for teosinte are not available, but the 

 coefficient of 0.69 in the hybrid material affords some evidence of coherence 

 between these characters. 



The correlations of total leaves with other characters are similar to 

 those of height, with the exception that there is no evidence of disherence 

 with nodes silking index. There is also coherence with branch silking first. 



