JANUARY 17 



The experiment was afterwards tried on a green lawn. 

 Of two potatoes painted to match the grass, one was 

 painted white on the underside. This one became 

 practically indistinguishable at a little distance, while 

 the other one, all green, was plainly seen, and appeared 

 much darker than the lawn. 



This experiment, which anybody may try for himself, 

 is remarkable, not only for its simplicity, but because 

 of its suggestiveness. That hares, deer, partridges, and 

 female water-birds should be closely assimilated to the 

 background of their breeding haunts is a striking 

 instance of provision for the protection of the species ; 

 but people are apt to view it vaguely as the result of 

 an automatic process such as causes all the book-backs 

 in a venerable library to assume a generally uniform 

 complexion. Here, in the whiteness of the underparts, 

 we seem to touch on evidence of a deeper and more 

 deliberate design; the stratagem of an external in- 

 tellect to neutralise the danger arising from the law 

 of light and shade. To hold that the prevalence of 

 white underparts had an accidental origin seems to 

 strain to the utmost the doctrine of evolution and 

 survival of the best protected ; although, on the other 

 hand, it may be claimed as additional evidence in 

 favour of that doctrine. It will be observed, by the by, 

 that white waistcoats have never come into favour 

 among grouse. On the contrary, living as they do 

 among dark heather and darker peat, they have 

 nothing to fear from their own shadows. 



Talking of protective coloration reminds one of the 



