COAT COLOUR IN GREYHOUNDS. d 



ever stand at stud, and, of these, only very feAV have a sufficient 

 number of mates upon which an assumption of pure dominance 

 couUl be based. For these reasons it may be taken that the 

 parents concerned in the 500 black to black matings were impure 

 dominants in gametic composition. The 500 matings yielded 

 3603 whelps, and, on the basis of the classical Mendelian ratio 

 of 3:1, the expectation is that there would be 2700 blacks to 

 900 brindles, red or fawns, and whites. The observed results 

 gave 2697 blacks and blues to 906 brindles, red or fawns, and 

 whites. 



In the black to blue matings, of which there were 231, there were 

 1338 whelps, and the expectation is the same as in the black to 

 black matings : namely, three blacks and blues to one other colour. 

 This would give 1003 blacks and blues to 335 brindles, red or 

 fawns, and whites. The actual results were 998 to 340. 



These figures clearly establish the premise that black is the 

 epistatic colour, and is dominant over all others. 



Take next the matings of black to brindle. The case here 

 is one of an impure dominant to a recessive, so that the 

 resulting offspring should be an equal number of impure domi- 

 nants and of recessives. That is to say, there should be an equal 

 number of blacks and blues to brindles, red or fawns, and whites. 

 The number of whelps in the 500 matings was 3053, so that there 

 should have been 1526 of each. The actual result was 1533 

 blacks and blues to 1520 brindles, red or fawns, and whites. 



Ln the black to red or fawn matings the case is again one 

 of impure dominant to recessive. Again equality would be 

 expected, so that of 3039 whelps there should be 1519 of each. 

 The actual result was 1525 : 1514, 



These figures still further conclusively prove that black is 

 epistatic to brindle and to red or fawn, 



Take now the blue matings. I have taken up the black 

 to blues. In the. blue to brindle matings the case is one of 

 impure dominant to recessive, and the expected result from 

 1293 whelps would, therefore, be 646 blacks and blues to 646 

 brindle, red or fawns, and whites. The actual result was 

 649 : 644. 



Blue and red or fawn matings fall into the same scheme, and 

 from 1822 whelps the result should have been 911 : 911, whereas 

 it was actually 915 : 907. 



The blue to blue matings only numbered 25, and resulted in 

 132 v/helps. Here the scheme is impure dominant to impure 

 dominant, which should give 3 blues and blacks to 1 brindle, 

 red or fawn, and white. The expected result was therefore 

 99 blues and blacks to 33 brindles, red or fawns, and whites. 

 The observed result was 93 to 39. 



In the table it will be seen that in these matings there were 

 6 blacks and 1 black and white, and this, or these, raise a 

 difficulty. Blue is undoubtedly a dilute black, and the previous 

 small incidence of blues clearly shows that if there is a special 



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