1 92 MAIZE 



CHAP, obtained a total of 672 normal-leaved and 221 liguleless- 

 leaved plants ; to have given as nearly a 3 : 1 ratio as possible 

 the respective numbers would only have to be changed to 670 

 and 223. 



151. Physical Condition of the Starch. — Presence and ab- 

 sence of starch, as we have already seen, behaves as a Men- 

 delian allelomorphic pair ; the presence of starch is a filial 

 character, and shows as xenia in individual seeds. East and 

 Hayes find, however, that the physical condition of the starch 

 behaves as a plant character affecting the whole ear : — 



" The characters which give the flint or the dent appear- 

 ance to maize are transmitted as plant characters to the entire 

 ear and not as endosperm characters to the seed. They 

 conform to the essential feature of Mendelism by showing 

 segregation ; and they are due to the action of more than 

 one transmissible character. The question remains, can any 

 or all of these characters be named? Our experience suggests 

 that the proportion of corneous starch to soft starch depends 

 partially upon size and shape of the pericarp, and upon the 

 number of rows per ear. . . . There is also some relation 

 between -the size of the plants and the amount of soft starch 

 in their seeds. . . . Relationship between the physical char- 

 acter of the starch and shape of pericarp is much more intimate 

 than it is between the former and size characters. . . . The 

 shape of the pericarp depends somewhat on the number of 

 rows, as the greater this number the more the seeds are 

 crowded together and thus lengthened. . . . These relation- 

 ships may simply be correlations and not direct causes of 

 the proportion of corneous starch to soft starch that exists 

 in various strains of corn. But even if they were directly 

 concerned, they could not account for the large number of 

 differences in varieties, for none of the correlations are suffi- 

 ciently high. Many other characters, the exact nature of 

 which is unknown, must be concerned in the matter. The 

 simplest interpretation . . . seems to be the interaction of 

 independent allelomorphic pairs, of the nature reported by 

 Nillson-Ehle (1) and East (4) in earlier papers." 



152. Size Characters. — Among size characters are in- 

 cluded : height of plant, number and length of internodes, 

 thickness of stem, breadth and length of leaf, length of sheath, 

 length of ear, number of rows per ear, thickness of cob, size of 

 seed, etc. 



