LINKAGE 



71 



large number of species in which Mendehan inheri- 

 tance has been discovered; but there are several rea- 

 sons whv more cases have not been recorded. In 

 the first place J the number of chromosomes is generally 

 large compared with the number of characters that 



Fig. 27. — Barred Plymouth Rock female by Langshan male. Compare 

 similar cross in Abraxas for scheme of inheritance. 



have been studied in such a way that linkage would 

 be noticed. Thus, there is little chance of finding 

 two factors lying in the same chromosome. Sec- 

 ondly, unless this linkage is close, it might easily 

 escape detection, especially when the number of o&- 



