194 



MENDELISM 



allelomorph respectively, since half the offspring ob- 

 tained on mating the blue birds with black are black, 

 and half the offspring obtained on mating them with 

 splashed white are splashed white. The following 

 scheme of inheritance illustrates the phenomena 

 described i 



i (zygote) 



blue heterozygote 



wnuc 



/white 

 \white 



A case which is closely similar to that of the An- 

 dalusian fowl is afforded by the cross between Primula 

 sinensis and Primula stettata. 



P. sinensis crossed with P. stettata gives rise to a 

 type which is different from either parent, being in 

 some respects intermediate between the two. The 

 hybrid is so distinct that a special name has been given 

 to it, and the new type is known as P. pyramidalis. 

 So far it has been found impossible to obtain a strain 

 of P. Pyramidalis which will breed true. On self- 

 fertilization the offspring are found to show the types 



