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in the green grass and in the green leaves of a green colour, and 

 those living in the sand of the colour of the sand, and so on 

 throughout all orders of creation. By protective resemblance 

 we mean the resemblance to their surroundings, which enables 

 animals to pass imobserved by their enemies and so escape 

 destruction. The cases of the hare, lemming, stoat, and many 

 other animals in northern latitudes are excellent illustrations ; 

 these become white every winter and brown every summer. It 

 is obvious that a brown hare in a snow-field would be a very 

 conspicuous animal, and that the palest members of the species 

 would be those that would escape destruction ; and the next year 

 the palest of the survivors ; and so on from year to year and age 

 to age until in time all would naturally become white as the 

 snow through natural selection or the survival of the fittest. And 

 the same reasoning as to white hares in brown heather will apply, 

 until natural selection has brought it about that all these 

 animals become white in winter and deeper coloured in summer. 

 A very curious theory, and apparently a very accurate one, has 

 lately been expounded by an American artist, Mr. Abbot H. 

 Thayer, as to the reasons for the white bieast and abdomen of 

 so many birds and mammals ; he says it is undoubtedly a pro- 

 tective quality. He has presented to the British Museum and to 

 the Museums of Oxford and Cambridge models of a bird in 

 duplicate, one coloured all brown, and the other brown above 

 with white breast and abdomen. The former is dark and dis- 

 tinctive and a prominent object at a distance ; the latter is 

 ghost-like, not very distinct when quite close, and rapidly fades 

 out of sight as you move away from it ; the white beneath 

 neutralises the shadow of the creature and thus makes it in- 

 visible, and makes it a beautiful example of protective resem- 

 blance, whereas the brown belly intensifies the dark colour." 



Pictures of several species of a low order of life, notably 

 insects and crabs, in which the resemblance of the animal to its 

 surrounding conditions acted as a protection to it, were thrown 

 on the screen. Then followed slides illustrative of the Lecturer's 

 argument as to aggressive resemblance, where the colour of the 

 creature, harmonising well with its surroundings, enabled it the 

 more easily to come at its prey. Colonel Swinhoe was careful 

 to point out that in many cases the similarity was doubtless both 

 protective and aggressive. The second set of pictures included 

 representations of the walking turtle and of certain fish. 



As regarded Mimicry in Nature two theories were put 

 forward. One, propounded by an entomologist named Bates in 

 1862, suggested that creatures specially appetising as food to 

 their neighbours are protected by their resemblance to creatures 

 of a noxious order in whose company they live. This extra- 

 ordinary theory was advanced by Bates, who was a close observer, 



