Sex-limited inheritance in Lychnis dioica L. 283 



or heterozj'gous condition of their broad-leaf determiners. I iiave tliree 

 such crosses to report at present, and have made the requisite pollina- 

 tions to test the condition of the males in all of the othei' independent 

 strains in my hands. I will greatly appreciate the consideration of any 

 one who will send me seeds of other strains of Lychnis dioica from as 

 many localities as possible, in order that similar tests may be made upon 

 them to ascertain whether the males of this species have the same geno- 

 tjTjic configuration, generaUi/, with respect to the F and B genes. 



The three Fi families produced by crosses of males or hermaphro- 

 dites of independent families, upon heterozygous broad (X nan-ow) -leafed 

 females, may be given separately as follows: 



(1) Pedigi-ee Numbers: 10244 (9) X 1090 (64) = 11334. The mother 

 of tliis cross was a female in my Fi broad (X narrow) -leafed family 

 reported above, for which the seeds were sent me by Dr. Baub in 1911. 

 The father was a white-flowered male in a family representing a com- 

 bination of two strains coming originally from Cold Spring Harbor, 

 Long Island, and from Harrisburg, Pennsylvania, respectively. The seeds 

 were sown early in March 1912 and produced 20 plants, all of which 

 bloomed. There were 14 broad-leafed females, 5 broad-leafed males and 

 1 narrow-leafed male. The numbers are too small to be of much value, 

 but the parallel with the family No. 11335, which was the offspring of 

 the same mother, is striking. The single narrow-leafed male was in all 

 respects tjT)ical of the angustifoUa-iorm. It had a bristle .5 '5 mm long 

 as compared with 2"0 — 3 •■5 mm in its five male sibs. Its occurrence in 

 this family indicates that the father was probably heterozygous for the 

 gene B, although certainly separated by a very long series of intervening 

 generations from any individual wliich could have been in the ancestral 

 line of the Sadowa plants which gave rise to the narrow-leafed mutant. 

 Since only one naiTow- leafed plant appeared in this pedigi'ee it is not 

 absolutely impossible that it may have been itself a mutant. Five narrow- 

 leafed individuals were theoretically due to appear if both parents had 

 been heterozygous, but as we have already seen, angustifolia is a weaker 

 form than "fij2nca" and is consequently usually deficient in numbers. 



(2) Pedigree numbers: 1133.5 (13) X 11 127 (11) = 12260. The 

 mother plant (11335 (13)) is shown above in Tables I and III to have 

 been heterozygous for the gene B. The father was a hermaphrodite 

 containing elements derived from the two original strains mentioned in 

 the last paragraph, but tracing back in one line to my original her- 

 majdirodite mutants discovered in 1908 in pure cultures of the Cold Spring 

 Harbor strain. The seeds were sown in February 1913, and yielded 



20* 



