A Genetic Study of Plant Height in Phaseolus Vulgaris. 45 
guarded pedigree cultures which had been under observation for 
two generations, except the July plant, in which case the pedigree 
ran back only one generation. 
The records reported here were made in 1912 from plants 
grown in the garden. All the families containing pole beans were 
grown together in a small part of the garden. Owing to lack of 
room in this place, the bush-bean families were grown a few rods 
away on practically the same soil but where exposure to the 
wind was somewhat greater. Tho the differences were not great, 
the conditions as a whole were somewhat more favorable where the 
pole-bean families were grown. Even in this small part of the 
garden, the conditions with respect to soil moisture were not as 
uniform as desirable. Owing to the dry weather, all the plants 
were irrigated early in the season and again later. One end of 
the pole-bean garden was more difficult to irrigate thoroly than 
the rest and, in consequence, received somewhat less water. 
Fortunately the different races and crosses were arranged in 
planting so that all of them extended across both the drier and 
moister parts of the' garden, except the Fi families which, owing 
to the small number of plants, did not extend entirely across the 
garden. For this reason, as well as because of the small numbers 
grown, the records of Fi plants are not entirely comparable with 
those of Fo and of the parent races. The plants of each parent 
race and of each Fo generation formed two rows across the garden. 
The records for these several lots are, therefore, it is believed, 
fairly comparable, tho the amount of variation within all the lots 
was increased to a certain extent by the somewhat unequal 
conditions at the two ends of the garden. 
In Table 4, are presented the data obtained from the four 
races and their crosses with respect to mean lengths of the first 
five internodes. As thus determined, the mean internode length 
of the bush-bean races was 24.41 ±0.31 mm. for Red Marrow and 
14.28^0.24 mm. for Triumph. The F2 generation of the cross 
between these races had a mean internode length of 19.53 ±0.39 
mm., almost exactly half way between the means of the parents. 
The range of variation in F2 extended from the lower extreme of 
Triumph to the upper extreme of Red Marrow. The standard 
deviation and coefficient of variation of the F2 plants were some- 
what greater than those of either parent and considerably greater 
than the parents' average. Evidently internode length in bush 
beans is inherited in much the same way as internode length in 
maize and as many quantitative characters in various plants 
are known to be (Emerson and East 1913). 
The pole beans, July and Snowflake, and the cross between 
them present a different condition. True, the mean length of the 
