10 Nebraska Agricultural Exp. Station, Research Bui. 7. 
This account deals with beans alone. Similar investigations 
are under way with maize in which are concerned both large and 
small ''dwarfs" as well as ''tall" plants of various heights. 
These studies have not been completed, but it seems unlikely 
that the results can be interpreted in quite the same way as are 
the results with beans. 
PREVIOUS INVESTIGATIONS. 
Mendel (1865) reported the results of a cross between a tall 
form of the common bean, Phaseolus vulgaris, 10-12 feet high, 
and a dwarf form of the same species (known then as P. nanus). 
He found tallness dominant to dwarfness in Fi and approximately 
three tall plants to one dwarf plant in F2. All F2 dwarfs remained 
constant in F,3, as did some of the talis, while the rest of the F2 
tails segregated again in F3. Mendel also crossed a dwarf form 
of the common bean with a tall, twining form of the runner bean, 
P. multiflorus. Owing to partial sterility, comparatively few 
individuals of this cross were grown. The results, however, were 
in very close agreement with those obtained from the cross 
between tall and dwarf forms of the common bean. In short, 
Mendel's results with beans were of the same sort as those of his 
more extensive and better known experiments with peas. 
Von Tschermak (1904) also crossed a dwarf race of P. vulgaris 
with a tall race of P. multiflorus. Here again tallness was domi- 
nant, tho somewhat weakened, in Fi, but the results in F2 were 
very different from those reported by Mendel. Of 144 F2 plants 
only 26 were classified as tall and 118 were short, or a ratio of 
1:4.5 where a 3:1 ratio was to have been expected. Of the short 
F2 plants about one-third were constant in F3 and two-thirds 
segregated again, a preponderant majority of their progeny 
being short and only a few of them tall, with occasional prostrate, 
very dwarf, giant, and intermediate plants. The tall F2S segre- 
gated in F3 into a majority of tall, twining plants and a minority 
of short plants. Irregular F3 progenies were also produced by 
the very tall, the very dwarf, and the intermediate F2 plants. 
In a later paper, von Tschermak (1912) presented additional 
data from another cross between a short common bean and a 
tall runner bean. Fi plants were intermediate but nearer the 
tall parent than the short one. Of the F2's, 35 were classed as 
short, 2 as intermediate, and 18 as tall. F3's from F2 short plants 
were, with the exception of one tall plant, all short. About 
four-fifths of these short Fs's were constant in F4, but one-fifth of 
them produced both short and tall plants, 58 of the former to 
4 of the latter. The tall F2 plants produced in F3 45 short, 23 
