HIS THEORY OF HEREDITY 121 



concludes that whilst some strictly follow Mendel's 

 laws, others obey certain other laws which are not 

 to be exactly formulated as those of Mendel. 



One last instance may be given to show the re- 

 markable differences of opinion which may be 

 held by men of science as to the interpretation of 

 the same set of facts. Mr. Hurst, a well-known 

 worker and an adherent to Mendelian principles, 

 and the late Professor Weldon, an equally stout 

 opponent of the same, both conceived the idea of 

 studying the inheritance of coat colour in horses. 

 Obviously to work this out by the ordinary method 

 of experiment would take at least one long life- 

 time, not to speak of great expenditure of money, 

 so both of them had recourse to the pages of a 

 work known as Weatherby's General Studbook of 

 Horses. It appears that this magnum opus runs to 

 twenty volumes, and gives " fairly complete records 

 of the age, colour, sex and parentage of British 

 thoroughbreds from the earliest accounts down 

 to the end of 1904." Their conclusions will be 

 found in the Proceedings of the Royal Society. * 

 Both, as has been stated, dealt with the same series 

 of facts, and both arrived at opposite conclusions. 

 Mr. Hurst thought that the Mendelian laws had 

 been justified ; Professor Weldon was of opinion 

 that they could be shown not to apply. No doubt 

 in this case the evidence is second-hand. The 

 colours of the race-horses dealt with were given 

 for other than scientific reasons, and probably no 

 one would have been more surprised than the 

 estimable Mr. Weatherby, or whoever may be 



* Series B, vol. Lxxvii. 



