394 



C. H. DANFORTH 



Pygopagus parasiticus type, which, however, produced only 

 normal young. She was a small hen with a rose comb and the 

 plumage of a barred Plymouth Rock. She was not brachy- 

 dactyl, polydactyl, nor booted. The father (no. 5) was white 

 with a pea comb and unusually heavy feathering on the neck, 

 suggesting Asiatic blood. He was of moderate size, polydactyl, 

 and booted. This is all that ca,n be said of the ancestry of no. 8, 

 the individual which supplied the traits studied in this paper, 

 but the nature of the experiments is such that a more com- 

 plete pedigree would be of little additional value. Male no. 8, 

 was hatched in 1914. His coloring was approximately that 

 of a barred Plymouth Rock, but with the breast somewhat 

 spotted and with more or less white in the hackle, saddle feathers, 



TABLE 1 

 Comparative statement of the conditions of each experiment 



^ This is exclusive of one day when, in the absence of the writer, only a single 

 alcohol treatment was given. 



and tail. His comb was large and corrugated, intermediate 

 between rose and walnut. He was polydactyl, grade 1 (left 

 foot only); booted, grade 2, and with a brachdactyly index of 

 88. In view both of his ancestry and his descendants, it is 

 clearly apparent that this bird was heterozygous for brachy- 

 dactyly and for Polydactyly. 



The homozygous parents were thirteen pure bred white Leg- 

 horn hens of a standard strain. There can be little doubt as 

 to the purity of this stock, especially as regards the characters 

 under investigation. 



In this experiment it was to be expected that the germ cells 

 produced by the females would all be of the same class, while 

 those produced by the male would fall into several classes 



