544 THE ZOOLOGIST. 



directions. This may even occur in an unexpected way, as in the 

 observation of Col. Pollok, cited by Mr. Distant, that the Tiger has 

 not yet learnt that in pursuit of game nothing can be done down wind. 

 Considerations such as these must lend a certain measure of support 

 to the mechanical conception of natural selection. Thus, in the matter 

 of conscious resemblance, although many animals may show undoubted 

 intelligence in other directions, it is highly probable that, in the great 

 majority of cases, their reasoning powers would not be sufficient to enable 

 them to decide whether, or no, their own colouring would have a pro- 

 tective value in any new or unusual environment, It is far more 

 reasonable to suppose that such knowledge as they may have in this 

 respect would be acquired through their experience of their liability to, 

 or immunity from, attack under such conditions, quite apart from any 

 colour considerations. The former process would be a true instance 

 of " active mimicry," as defined by Mr. Distant, but the latter cannot 

 be included under that term ; indeed, in such cases, experience in the 

 individual is the equivalent of natural selection in the species. 



In the preliminary portion of his paper, Mr. Distant has given us 

 many excellent examples and arguments to show that mimicry and 

 protective resemblance probably existed in very remote antiquity ; 10 

 and he has done well in drawing attention to the matter, which is apt 

 to be overlooked. But I must certainly join issue with him when he 

 states that : " The present attitude of many champions of the cause, 

 who seek to find, or to invent, present factors for producing these 

 phenomena, seems fraught with peril for the whole theory ; and, with 

 the same weariness and perseverance with which the original promul- 

 gators thought out the doctrine, we must go on searching for further 

 proofs, which will necessitate our appealing to the Caesar of the past — 

 the ever-growing science of palaeontology " (/. c, p. 302). I must con- 

 fess that this appears to me to be a very remarkable assertion. In the 

 first place, the vast majority of cases generally referred to mimicry and 

 resemblance are concerned with colour and movement alone, structure 

 playing but a very subordinate part therein.* Mr. Distant has himself 

 been at some pains to show the very evident futility of appealing to 



* The point discussed was the structural characters of the Phasmidae. The 

 exact quotation requires this antecedent: "We still have abundant reason 

 for believing that, though the protective resemblance of these Phasmidae was 

 already acquired in Carboniferous times, the presence of Amphibia in an 

 evolutionary sense is quite sufficient to account for it. This prompts two 

 reflections : one, that we ought to look a long way back for the origins of 

 these protective and mimetic guises ; and the other, that we may reason- 

 ably hope to find them " (p. 302). — Ed. 



