1012 JOURNAL, BOMBAY NATURAL HTSTORY SOCIETY^ Vol. XJX. 



I venture to suggest that those who agi-ee with them in this matter do so under 

 a partial misconception of the foundations upon which the theory of protective 

 colouration is built. That there is such a misconception I hold to be proved 

 by the presence of the following sentences culled from the two authors. 



Col. Burton, in the above quoted contribution, en page 401, writes "I am 

 inclined to think that colouration is far more due to environment, to the colour 

 of the surroundings and to climatic causes, than to sexual seleciion for protective 

 purposes. " 



Mr. Selous, in his " African Nature Notes and Reminiscences " says, on page 



5, line 1 . " , . . . The colour of the leucoryx has not been 



brought about in order to serve as a protection against enemies. " (In both 

 cases the italics are mine.) 



I think the misconception in either case is patent, though peihaps the word 

 sexual in the first quotation is a clerical error and should read miivral. It 

 appears to me that both authors have misundeistood the theory of protective 

 colouration by adaptation through natural selection. 



It is perhaps possible to agree that some naturalists have claimed to explain 

 too much by the light of this hypothesis, but, reading carefully through Mr. 

 Selous two chapters on protective colouration, the impression created is that 

 he rejects protective colouration altogether, though not positively stating 

 the fact. 



Now it is quite possible that environment has some irfluence on the coloura- 

 tion of animals (though that has to be proved as well as the exact agency 

 through which it acts) ; but this in no way affects the theory of protective 

 colouration, rather the contrary. 



Every one will admit that if it is environment that influences colouration, it 

 must do so in a great variety of shades to account for the great differences in 

 tlie colour of aaimals inhabiting the same locality, e. g., tiger, san.bar, sloth 

 bear, bison, etc., in India ; and the divergence is still more striking in South 

 Africa with the lion, the zebra, the buflalo and the various splendidly coloured 

 antelopes living in the same plains. 



This being so, then either all animals, under this influence, should eventually 

 assume the same coats, or else external specific features must tend to disappear 

 as there is nothing to fix the colour, which may, at any time, be gradually 

 changed to any of the other colours brought about by the particular environ- 

 ment. 



We here come to the " clou :" there must be some force or influence to fix 

 a particular colour and we have that agency in natural seleciion. 



Nothing is more certain than the fact that constant slight variations in dimen- 

 sions as well as in colour do crop up among animals of the same species. 

 Probably no two individuals are exactly alike in every respect. No one will 

 quarrel, I think, with the assertion that no variation, however slight, can fail 

 to reach in some, way on the organism in which it appeals. In the vast 

 majority of cases, however, this reaction is so infinitesimal that it may be 



