20 Varietäten, Descendenz, Hybriden. 



a sijrnificant deviation in the number of sweet seeds, the observed 

 number is below the expected. Reasons are advanced for believing 

 that the deticiency of the sweet class may result from a failure ot 

 sorae sweet seeds to develop a wrinkled exterior rather than from 

 any irregularities in segregation. 



The results show the value of representing the characters by 

 gametic factors. This method provides an orderly arrangcment of 

 the facts of heredity thus far observed with respect to these charac- 

 ters and makes possible fairly accurate predictions regarding the 

 genetic behaviour of the various seed classes. Jongmans. 



Emerson, R. A., The inheritance ofarecurringsomatic 

 Variation in variegated ears of Maize. (American Natu- 

 ralist. XLVIII. p. 87—115. 1914.) 



A somatic Variation in maize is shown to be inherited in simple 

 Mendelian fashion. The Variation has to do with the development 

 of a dark red pigment (or in one stock a brown pigment) in the 

 pericarp of the grains, often associated with the development of an 

 apparently similar pigment in the cob and husks. 



Piants in which this pigment has a variegated pattern may 

 show any amount of red pericarp, including wholly selt-red ears, 

 large or small patches of seif- red grains, scattered seif-red grains, 

 grains with a Single stripe of red covering from perhaps nine 

 tenths to one tenth of the surface, grains with several prominent 

 stripes and those with a Single minute streak; ears with most of 

 the grains prominently striped and ears that are non-colored except 

 for a Single partl}'- colored grain, and probably also piants with 

 wholly self-red and others with wholly colorless ears. 



It is shown that the amount of pigment developed in the 

 pericarp of variegated seeds bears a definite relation to the deve- 

 lopment of color in the progeny of such seeds. This relation is not 

 such that seeds showing say nine tenths, one half, or one tenth red 

 will produce or even tend to produce piants whose ears as a whole 

 or whose individual grains are, respectively, nine tenths, one half, 

 or one tenth red. Experimental results indicate rather that the more 

 color in the pericarp of the seeds planted the more likely are they 

 to produce piants with wholly selfred ears, and, correspondingly, 

 the less likely to yield piants with variegated ears. 



Self-red ears thus produced are shown to behave in inheritance 

 just as if they were hybrids between self-red and variegated races 

 or between self-red an non-red races, the behavior in any given 

 case depending upon whether the parent variegated ears were ho- 

 mozygous or heterozygous for variegated pericarp and whether 

 they were self-pollinated or crossed with white. 



It is suggested that these results may be interpreted by the 

 assumption that a genetic factor for variegation, V, is changed to 

 a self-color factor, S, in a somatic cell. All pericarp cells directly 

 descended from this modified cell will, it is assumed, develop co- 

 lor, and of the gametes arising from such modified cells one halr 

 will carry the S factor and one half the V factor if only one of 

 the two V factors of the somatic cells is changed, or all such ga- 

 metes will carry S if both factors are changed. 



The V factor is thought of as a sort of temporary, recessive 

 Inhibitor that sooner or later permanently loses its power to inhibit 

 color development, becoming thereb}^ an S factor. Or it may be 



