34 Nebraska Agricultural Exp. Station, Research Bui. 7. 
habit, like July, would be subject to greater variation than plants 
of determinate growth. If this is true, the variation shown by 
the F2 bush plants of the cross between Red Marrow and July 
should be compared with that of the bush-bean parent, Red 
Marrow, rather than with the pole-bean parent, July. Such a 
comparison suggests the probability that the parents of this cross 
may have differed by one or more factors for number of internodes 
and that these factors segregated in Fo. 
Whether or not the variation noted in the F2 bush plants of 
the crosses discussed above indicates segregation of factors for 
number of internodes, there is less doubt in case of the cross 
between Red Marrow and Snowflake. The coefficient of variation 
of the F2 bush beans of this cross was 19.65 ±2.18 per cent as 
against only 10.76 ±0.57 for Red Marrow, a difference of 8.89 ± 
2.25. The genetic factors for number of internodes, in regard to 
which the parents of this cross presumably differed, must be 
distinct from the factor or factors concerned with habit of growth, 
for all these F2 bush plants must have lacked the factor for in- 
determinate growth and all must have had the factor for deter- 
minate growth. If this is true, the F2 pole-bean segregates of this 
same cross should also have shown greater variation than the 
parents. By reference to Table 2, it will be seen that this was 
actually the case. 
In Table 2 are given the frequency distributions for number of 
internodes of the pole-bean parents of some of the crosses dis- 
cussed above, of the Fi generation of these crosses, and of the F2 
segregates of indeterminate growth habit. The plants from which 
these records were made were all grown side by side in the garden 
in 1912. Owing to the small numbers of plants in individual 
families, the several families of each race and of one generation 
of each cross are thrown together, just as was done in Table 1. 
While it is recognized that this procedure is somewhat question- 
able, it is believed that the results are not vitiated materially 
thereby. 
The rather short pole bean, Snowflake, owes its low stature 
in part to a comparatively small number of internodes. The 
mean number of internodes was a little over 20. The much 
taller race, July, averaged somewhat over seven internodes more. 
The greater vigor of the Fi generation of the cross of these races 
resulted in an average of a little over 30 internodes. The Fi 
progenies of the crosses between the tall bush bean. Red Marrow, 
and these pole beans had slightly fewer internodes than July 
but considerably more than Snowflake. The Fi plants of the 
cross between the very short bush bean. Triumph, and the com- 
paratively short pole bean, Snowflake, were among the most 
