THE CASE OF THE BLUE AND ALUS IAN 1 



WILLIAM A. LIPPINCOTT 



Kansas Agricultural Experiment Station, Manhattan, Kansas 



The blue Andalusian has become the classic in animals 

 as an example of a heterozygote phenotypically inter- 

 mediate between the parental types. It has also served 

 as an illustration of the failure of dominance for those 

 opponents of Mendelism who consider dominance one of 

 its fundamentals. Furthermore, it has been in constant 

 demand as a classroom example of blended inheritance. 



The main facts concerning the breeding behavior of 

 blue Andalusians are, accordingly, more or less familiar. 

 In spite of the long-continued efforts of their breeders 

 they do not come true to color as a breed, but continually 

 throw a certain proportion of off-colored progeny, or 

 "wasters," of two kinds. One is self (entirely) black. 

 The other approaches white, but displays considerable 

 pigment, and is referred to variously as white, splashed, 

 and splashed-white. Since an examination of a large 

 number of birds of this type shows the pigmented feathers 

 to be bkie in all sections of the female and in those sec- 

 tions of the male which carry blue feathers in the blue 

 Andalusian male, they will be referred to throughout this 

 paper as blue-splashed. 



< ' Splashed" refers to the fact that the pigment does not 

 regularlv appear in any particular group of feathers or 

 in any definite region. Feathers located apparently at 

 random on any part of the body may be pigmented over 

 their entire surface or may show only slight traces of pig- 

 ment. Not infrequently both of these conditions are 

 present in the same individual. 



Since the blacks and blue-splashed breed true when 



