PROTKt;TI\'K RKSKMBLANt;K fN Mo I'HS. 176 



the evidence we require is whether they systematically search for them 

 when settled on walls, tree-trunks, and the like. Mr. Coltbrup doubts 

 that they do, with the exception perhaps of the Tits; T am inclined to 

 agree with him, but my experience of English moths is limited. If a 

 moth with closed wings resembling a lichen is as free from attack on a 

 brown plank as it is on a lichen covered tree-trunk (a somewhat bold 

 assertion) of what use is its protective pattern and how did it become 

 evolved ? That it obtains some protection is hard to deny, but how 

 much is a difficult matter to estimate. 



The acknowledgment that even a, slight variation in colour or 

 pattern is advantageous is sufficient in the minds of many to eonfirui 

 them in their belief in natural selection, particularly when they 

 remember the infinitely slow methods of Nature, and the unlimited 

 time at her disposal. The case has been well put by Wallace.* "In 

 every department of Nature colour is one of the most variable of all 

 characters, and it is this variability, together with the enormous im- 

 portance to all insects of concealment from, or protection against, their 

 innumerable enemies, especially in tropical countries, that has enabled 

 those minute and striking resemblances to be brought about that were 

 long the greatest puzzle to those naturalists who had the opportunity 

 of observing them in their native haunts. The facts already given 

 with regard to the universality of variation, enormous powers of 

 multiplication and incessant weeding out of the unfit, afford a com- 

 plete explanation of the phenomena of colour, in all their variety and 

 beauty, which no other adequate explanation has ever been set forth, 

 or even attempted." If there is one thing more than another which 

 has impressed me, durmg my twenty years' wandering in the tropics, 

 it is the haphazard way in which death comes to the animal world. 

 From the elephant downwards it has always seemed to me an entire 

 matter of chance; though it might be mathematically proved that in 

 the long run an animal most fitted to its environment would have an 

 advantage, yet, life in the jungle is such a lottery, that, so far as 1 

 have observed it, it is merely a toss up as to what lives or what dies. 

 It is true that a tiger, acting alone, will avoid attacking a full grown 

 bull bison, and will take a calf in preference, but what calf is taken is 

 a matter of chance ; so also two tigers acting together will pull down 

 a bull bison but it is a matter of chance as to what bull they first 

 happen to come across. 



My own experience of birds eating moths in large numbers is 

 confined to Ceylon, but the conditions were entirely artificial. It was 

 at the time of the internment of the Boer prisoners in 1901-2. Their 

 camp was in a fold of the hills at an elevation of 4,000 feet in an 

 open country. The barbed wire entanglement was lighted up by 

 large arc lamps on posts twenty feet high at intervals of about fifty 

 yards, and gave a very fine illumination. For some reason they failed 

 to attract any large number of moths except in late October and early 

 November; with the setting in of the North-East Monsoon, towards 

 the end of this month, a dense fog arose every evening, which blotted 

 out everything. Fortunately for the moth population the attractive 

 season was remarkably short, but while it lasted the state of affairs 



* The World of Life, a.i Vistialiicd attd Interpreted bij Darwinism, A. K. 

 Wallace, Fortnightly Review, March, 1909. 



