300 



Journal of Agricultural Research 



Vol. IV, No. 4 



EXPLANATION OF SYMBOLS AND FACTORS IN TABLE H 



All of the second-generation hybrids of this series contain more red than the cor- 

 responding hybrids of the former series. This additional red unquestionably comes 

 from the Coccinea parent. There are not sufficient data to determine what this 

 additional red is and its entire behavior in heredity. 



The factors E, e, B, b, R, and r have a similar significance to that in Series I, 

 although they are evidently not exactly the same. Plants in Series I and II having 

 the same phenotypic formula are not identical, as may be seen from the illustrations. 

 This indicates that the factors of the two series are not identical. 



Observed and Calculated Ratios 

 The calculated and observed ratios correspond very closely in this 

 series. This is the more evident when the relatively large number of 

 classes and the small number of individuals are taken into account. 

 Grouping the data as before gives the following results: 



E e R r Pigmented White 



Observed 82 3^ 89 26 108 7 



Calculated 86. 3 28. 7 86. 3 28. 7 107. 8 



7.2 



SERIES III 



Pollen parent. — The same variety, Carnea, as used in Series I and II. 



Seed parent. — A yellow variety known commercially as Large 

 Yellow. The pigmentation is more dense at the center eye than at 

 other parts of the flower (PI. E). 



Table III. — Color of the progeny of two varieties of Phlox drummondii , the Large 



Yellow and the Carnea 



Parent or progeny. 



Seed parent: Phlox drum- 

 mondii, var. Large Yellow. 

 Pollen parent: Phlox drum- 

 mondii, var. Carnea. 



Fi generation 



F2 generation: 

 Alternative factors — 

 (Y 



Phenotypic 

 formula. 



ErY 



eRy 



EeRrYy. 



EERRYY. 

 EERRyy.. 



EErrYY. 

 EErryy. . 



eeRRYY. 

 ecRRyy . . 



eerrYY. 

 eerryy. . 



Phenotype. 



Cream yellow (30-3), dark eye. 



Pale rosy-pink (129-1). white 



eye. 

 Rose Neyron red (119-2), dark 



eye. 



Deep lilac rose (151-2), yellow 

 (dark) eye (PI. E, fig. A). 



Pale pink (13 5-1), dark eye 

 (PI. E, fig. B). 



Cream yellow (30-4), dark eye 



(PI. E. fig. C). 

 White, dark eye (PI. E. figs. 



D and E). 



Lilac purple (160-2), white eye 



(PI. E, fig. F). 

 Pale reddish lilac (131-1), 



white eye (PI. E, fig. G). 



White (PI E, fig. H) . 

 White (PI. E, fig. H) . 



Field 

 count. 



Calcu- 

 lated. 



39-69 

 13- 23 



13- 23 

 4.41 



13-23 

 4.41 



S-8S 



Ratio. 



64 



EXPLANATION OF SYMBOLS AND FACTORS IN TABLE III 



In addition to the factors already mentioned, we have a factor for yellow (Y), 

 which acts only in the presence of the eye factor (E). Wherever Y is present and E 

 is absent, only white occurs. 



