36 REPORT ON THE CONFERENCE ON GENETICS. 
into lax, intermediate, and dense. In the F, the extreme lax or dense 
ears are found to breed true, whilst the intermediates break up into the 
three forms again. A series of sowings shows that these three types 
probably occur in the ratio of 1: 2: 1. 
H. nutans x H. deficiens. 
In H. nutans the lateral florets are staminate, and in H. deficiens 
sexless. 
F,. Lateral florets small and sexless, but more developed than in 
HI, deficiens. 
F,. Segregation into three groups with staminate, small and rudi- 
mentary lateral florets in the proportion of 1: 2:1. The forms with 
the small laterals again split in the next generation. 
H. parallelum x H. decipiens. 
In H. parallelwm the lateral florets of each triplet are hermaphrodite 
and set grain. In H. decipiens the median floret only is hermaphrodite 
and the lateral florets are rudimentary. 
F,. The lateral florets are staminate, as in the group H. distichon. 
F,. Fertile lateral florets, staminate and rudimentary occur in the 
proportion of 1: 2: 1. 
F,. The forms with the fully fertile and those with rudimentary 
florets breed true, whilst those with staminate laterals give the same types 
as before. 
H. vulgare x H. Steudeli. 
Parents: White, lateral florets fertile. Black, lateral florets sterile. 
Fy :— 
Black, with fertile laterals, 24 
White, with fertile laterals, 6 
Black, with sterile laterals, 71 
White, with sterile laterals, 19 
HH. nigrescens x H. @ethiops. 
H. nigrescens, lateral florets male only; bearded. H. ethiops, lateral 
florets hermaphrodite and fertile ; hooded. 
F',. Lateral florets larger than those of H. nigrescens and frequently 
fertile (dependent on supply of nutriment ?); hoods on short awns. 
F,. Hooded and awned six and two row types with a series of 
individuals with occasionally fertile lateral florets. The extent to which 
these set grain is very variable. In the next generation these all prove to 
be heterozygotes. Six row, heterozygote, two row as 1:2: 1. 
H. wanthinium x H. utriculatum. 
H. ianthiniuwm, awned, purple; H. wutriculatwm, pale trifurcate 
(hood), white. | 
F,. Purple; the colour is most marked before the ears are dead ripe: 
hooded, the hoods sessile. 
