1/4 THE MUTATION THEORY 



parental differences is never alternative. As regards a few 

 features I can think only of eye-colour the characters of a dark 

 race may dominate over those of a light-coloured one; but the 

 dominance is permanent ; it is transmitted to all the members of 

 all succeeding generations that breed together. Therefore the 

 reproduction is not Mendelian. But as regards the great majority 

 of characters the blending is perfect and often nearly equal, and 

 as such is transmitted to the latest descendants. A race of per- 

 manent and patent mongrels is formed. If three or four races are 

 crossed together, as has happened in South America, each 

 contributes its quota in perpetuity to the blend. It is a common 

 belief amongst experimental workers that " a fusion of characters 

 is rather a rare phenomenon. Human skin-colour is the one 

 striking case." But really that is very wrong. Fusion is very 

 much the general rule, not the exception. 1 The fact that the 

 gametes of the cross blend " is as strong an indication as can be 

 desired of the ' continuity ' between them." 2 When the negro, for 

 example, crosses with a white race, the offspring, the mulatto, is 

 conspicuously a blend in all except eye-colour. His hair, it is true, 

 more closely resembles in texture the African than the Caucasian 



1 Strange as it may appear to people who have travelled in Asia, Africa, 

 America, Australasia, or Polynesia, experimental workers, or some of them, 

 express doubts as to whether human races really blend. " It would be extremely 

 interesting to students of genetics to learn upon what evidence Dr Archdall Reid 

 bases his positive statement that there is no segregation in the case of the Mulatto " 

 (Mr R. H. Lock, Nature, Oct. i/th 1907; see also Bateson, Mendel's Principles of 

 Heredity, pp. 208-9). " The evidence on which I base my assertion that there is 

 no segregation in the mulatto is that of my own eyes. Mulattos vary amongst 

 themselves, but the blend is usually very obvious and is reproduced in subsequent 

 generations when the breeding is inter se. With every infusion of European blood 

 the negro type skin colour, hair texture, shape of features, and [the like grows 

 fainter until at length the ' touch of the tar brush ' is hardly, if at all, perceptible ; 

 and this blending, as far as I am aware, occurs not only in all crossed human 

 varieties, but in other natural varieties as well. There may be exceptions, in 

 fact I believe there are ; but blending appears to be the rule in the vast majority 

 of instances " (G. Archdall Reid, Nature, Oct. jist 1907). " If Dr Archdall Reid 

 will produce authenticated pedigrees showing the repeated crossing of the mulatto 

 with pure white blood and pure black blood respectively, together with a detailed 

 account of all the offspring produced, he will make a very substantial contribution 

 to our knowledge of heredity in the human race, and one which will be examined 

 with very great interest by Mendelians " (Mr R. H. Lock, Nature, Nov. i4th). 

 " Since Mr Lock is probably the only human being who doubts the blending of the 

 black and white races in Mulattos and their descendants, it would be well if he, 

 rather than I, undertook the collection of pedigrees. He would feel himself on 

 the track of a great discovery which would enlighten even Mulattos, whereas I 

 should feel I was wasting time " (G. Archdall Reid, Nature, Nov. 2ist). 



* See footnote, 277. 



