538 
Journal of Agricultural Research voi. xxvn, no. 8 
of hybrids with the perennial species shows a much higher degree of 
dominance of all the characters of teosinte than has been found in hy¬ 
brids with the annual species. 
At the present time, F 2 populations have been raised from crosses of 
Euchlaena mexicana with golden (jj), ramose (9), brachytic (jo), rain¬ 
bow (j), and crinkly (7), while progenies have been grown with 
dwarf ( 6 ), and pod (14). 3 
In making these hybrids teosinte almost invariably is used as the fe¬ 
male parent, since in controlling the flowering stage of this species by 
shortening the length of day, the staminate flowers are suppressed. 
As teosinte has but from 7 to 10 seeds in each pistillate spike, only a 
few seeds are obtained as the result of each pollination; the first- 
generation populations therefore are small. In the crosses with crinkly, 
ramose, and brachytic maize, however, teosinte served as the male 
parent; with the crinkly an unusually large number of seeds were, ob¬ 
tained, in consequence of which a large population of this hybrid 
was grown. 4 The hybrids differ somewhat in general vigor and in the 
size of the plants,, one of the most vigorous being the crinkly cross, which 
seems to have commercial possibilities as a forage plant. In the char¬ 
acter of the inflorescences, all resembled the hybrid with Tom Thumb, 
with the exception of the cross with the dominant variation pod. , This, 
as was to be expected, produced long glumes on the pistillate spikes 
similar.,to those of a podded ear. These long glumes on the character¬ 
istic four-rowed, ear of the F t maize-teosinte hybrid give a rather start¬ 
ling resemblance to a gigantic wheat head (PI. i). 
, :j Tpe. hybrids jwith golden and rainbow, of course, were normal with 
respect to these.characters, and segregated in the F 2 into numerous grades 
of the parental colors, 5 In a population of 371 plants of the ; rainbow 
crops np plants as fully variegated as the maize parent were recovered, 
though many truly beautiful plants were produced. 
, In the hybrid with golden, plants were obtained fully as yellow as 
thepanent, if not more so, though there was no clear distinction between 
golden and green. The segregation in the F 2 of these hybrids suggests 
thnt JJyphlaena possesses modifying factors for both of these characters 
and,j as in other hybrids, the form of inflorescence seemed to be asso¬ 
ciated but loosely with the Mendelian characters under observation. 
The inheritance of the other three characters, crinkly, ramose and 
brachytic, is capable of quantitative analysis, which should offer more 
critical evidence pn the existence in Euchlaena mexicana of modifying 
factors for these characters. 
* Seed stocks of golden and crinkly were received from.R. A. Emerson, ramose from W. B. Gemert, 
pod fr6m H. S. Sconce, while rainbow was purchased from Xttther Burbank and brachytic and dwarf 
arose in our own pedigreed s^ock. The degree of yellow in the.original golden strain \vas somewhat, vari¬ 
able, but the strain finally used in the cross with Euchlaena was developed from the original stdck With 
rather, an extreme expression of the yellow pigment. The stock (rf rainbow purchased' from Burbank hat 
well-developed white and yellow stripes, together with the red plant color. The inheritance ot the 
japonica striping has been-reported by Eindstrom Qts), while that'of red plant color has been reported by 
Emerson (<£). The stock as originally received was heterozygous for red plant color, and for yellow as 
opposed to white striping. The degree of expression of all of these characters was variable, though no 
self-colorfed plants have been found in the original stock. Through selection and inbreeding it has been 
possible to isolate lines having almost chlorophyll-free upper blades, and others practically self-green. The 
seedling leaves of these divergent strains are very similar, perhaps the only difference being the rather 
earlier appearance of variegation in the extreme white strains. 
In the cross with Euchlaena a medium-variegated plant was used, being homozygous for red plant 
color and heterozygous for white and yellow stripes. 
4 These crosses were made by C. G. Marshall at Chula Vista, Calif., and the Fi and Fj populations were 
grown under his direction at the same place. 
6 The Fi plants of the hybrid with rainbow were red, as was to be expected, but were normal in that the 
striped condition of rainbow was completely recessive. 
