19 



as the numerous personal observations, more especially in the 

 valley of the Amazon. 



On all fours with it was the theory of Fritz Miiller, also 

 arrived at from much personal observation. This supposed that 

 a common type of appearance among distasteful insects in the 

 same locality acts as a common advertisement to enemies, so 

 that the loss of life which must ensue during the time in which 

 each generation of enemies is being educated to avoid the owners 

 of a particular type of pattern and colouring, is shared between 

 these species, instead of being borne by each of them indepen- 

 dently ; it is, in fact, a multiplication of protection. As might 

 be expected, all, or nearly all, animals protected by their dis- 

 tastefulness, are brightly coloured and mostly of distinctive 

 patterns. Professor Lloyd Morgan's and Mr. Finn's recent ex- 

 periments, made independently in different parts of the world, 

 prove that there is no inherited knowledge of suitability or 

 unsuitability for food, but that everything of an appropriate size 

 and at the right distance is pecked at and tasted by young birds ; 

 on the other hand, young birds are extremely quick in learn- 

 ing, and have very retentive memories. Furthermore, one 

 unpleasant experience makes them suspicious of other things, and 

 they remember well the appearance of the insect which gave 

 them a disagreeable surprise. 



What was true of birds was probably, said the Colonel, true 

 of other animals as well. 



As an illustration of Miiller's theory, he exhibited a few 

 groups of "distasteful butterflies," which were mimicked in 

 appearance by others which might otherwise prove too appetising 



to live. 



Moreover, from the various examples it appeared that 

 females were more frequently defended than males, a fact ren- 

 dered more desirable for them on account of their slower flight 

 when laden with eggs, and of other disabilities of their sex. 



In conclusion, Colonel Swinhoe pointed out that the theory 

 of mimicry and of common Avarning colours was believed by 

 scientists, not because we have demonstrative proof in a com- 

 plete knowledge of the details of the struggle for existence,— it 

 will be very long before we attain to this,— but for the same 

 reasons that we believe in evolution, because the theory offers an 

 intelligible explanation of a vast number of facts which are un- 

 explained by any other theory as yet brought forward, and 

 especially because it enables us to predict the existence of facts 

 which can afterwards verify. 



