3«8 
Journal of Agricultural Research 
Vol. IX, No. ii 
homologous to the branches of Z. ramosa. The branches in the ear of 
Z. tunicata are proliferated spikelets, while the branches of a ramosa ear 
are, like the branches of the tassel, divisions of the main axis with no 
evidence of a subtending bract. 
DESCRIPTION OF THE HYBRID 
The cross between Z. tunicata and Z. ramosa was made at Lanham, 
Md., in 1914. The female parent was a plant of Z. ramosa grown from 
seed supplied the Department of Agriculture by Dr. Gemert. The male 
parent was a plant of a tunicate strain developed by Mr. H. J. Sconce. 
The parent ear was what is here designated as half tunicate. 
Nine first-generation plants of this cross were grown at Chula Vista, 
Cal., in 1915. Of these, four were tunicate and five normal, indicating 
the heterozygous nature of the half-tunicate parent plant. The tunicate 
plants were all half tunicate, and no trace of the ramosa characters could 
be seen. 
Five self-pollinated first-generation ears were selected for planting in 
1916. Three of these ears were tunicate and two normal. The three 
tunicate ears all showed about the same development of the tunicate 
character. The seeds were all well covered by the glumes, but the 
longest glumes did not exceed 30 mm. 
The second generation was grown in 1916 at Lanham, Md. Four 
hundred and eight plants matured, 326 from the three tunicate ears, 
and 82 from the two nontunicate ears of the first generation. 
The progeny of the nontunicate or normal F t plants may be dismissed 
with the statement that the F 2 plants showed segregation into normal 
and ramosa in the ratio of 3 to 1, the numbers being 65 normal and 17 
ramosa. In none of these plants was there evidence of tunicate characters. 
The first impression to be gained from the descendants of the tunicate 
plants as they came into flower was that there was a completely hetero¬ 
geneous mixture of the characters of the two parents, together with many 
new monstrosities. On closer examination it soon became evident that 
there was one clearly defined group of plants having all the characters of 
normal maize. It was also possible to distinguish many plants with 
characteristic tunicata or ramosa tassels. Among the latter types, 
however, there were many intermediates, and in addition there was an 
entirely new type of inflorescence. In this new type the branching habit 
was developed to a grotesque extreme, As soon as branches formed 
these again branched. This division continued until the end of the 
growing season when the tissue was still in an embryonic condition, 
and nothing resembling floral or foliar organs was formed. The result 
was a white succulent mass (PI. 17, 18). This peculiar formation oc¬ 
curred in both lateral and terminal inflorescences, though it was much 
more common in the former, and in terminal inflorescences it was usually 
confined to the basal branches. 
