8 ESTABLISHMENT OF VARIETIES IN COLEUS 



tious variegation which is transmitted through both germ-cells to a 

 part of the progeny. 



Among the most interesting series of observations especially bearing 

 on the behavior of red coloration in Coleus and most important in the 

 consideration of the nature of variegation and the character of somatic 

 variation and the relations of these to seed progeny, is that of Emerson 

 (1914). The variegation in question is that of pericarp color in certain 

 "calico" races of corn. The extent of coloration varies widely, ranging 

 from solid red through every degree of striping and blotching to entirely 

 non-red, both for ears as a whole and for single kernels on the same ear. 



Emerson made careful studies of the progeny of seeds having different 

 degrees of coloration. His results show a wide range of variation in 

 the progeny of kernels that appear to be identical. Selected solid-red 

 kernels from " freak ears" of unknown parentage gave, in some cases, 

 progeny with only solid-red or non-red ears, and in other cases the 

 plants produced solid-red, variegated, or non-red ears. Variegated and 

 white kernels (data not given separately) gave either variegated and 

 white, or red, variegated, and white. Again, from two ears, kernels of 

 white gave progeny pure white, and red kernels gave red and white 

 only, each of which gave afterward a constant progeny. 



In selfed variegated strains, kernels of all classes from solid-red to 

 non-red gave progeny with ears solid-red or variegated, but none 

 with no-red ears. 



Data are given collectively for progeny of 5 solid-red ears (selfed). 

 These gave solid-red and variegated (p. 18). Progenies of only two 

 plants of these solid-reds are reported. One gave again plants with 

 solid-red or variegated ears, the other gave only solid red. The num- 

 bers grown in this generation were respectively 9 and 16. Emerson 

 considers from these data that, in general, red-eared plants behave, 

 judged by progeny, as if they were hybrids either between solid-red and 

 variegated or solid-red and white races. 



The data show quite clearly, as Emerson points out, that the more 

 red there is in the seed planted the larger the percentage of red ears 

 in the progeny. The variegated race is therefore far from constant. 

 Selection from red kernels and from red ears give a strain quite constant 

 for solid-red, but Emerson's data are far from conclusive that a pure 

 solid-red strain was obtained in this way. 



The results of crossing the variegated race with non-red races are 

 interesting. When the former was the pollen parent, the FI progeny 

 gave red, variegated, and non-red ears, but Emerson states that some 

 of the latter may have been extremely light types of variegation. 

 From the reciprocal cross selected kernels for the FI gave red and 

 variegated or only variegated. 



In the selections from hybrid stock, as in that in selfed stock, the 

 seed that had more red gave greater numbers of pure-red progeny. 



