184 Barbour and Phillips, Concealing Coloration Again. |_April 



We think we can account for the way in which secondary sex 

 characters are perpetuated, or perhaps even increased, on the as- 

 sumption (in polygamous forms at least) that those males with the 

 most marked sexual characters would tend to be the most vigor- 

 ous in a struggle for the other sex. But this assumption leaves us 

 completely in the dark as to the fundamental significance of sexual 

 dimorphism, and further speculation is out of place in the present 

 paper. We merely mention it to point out one of the biological 

 problems which Mr. Thayer, in his enthusiasm, has ignored or 

 glossed over with an artistic haze. 



Another phase of the question which Mr. Thayer ignores is the 

 question as to whether or not the habits of an animal demand pro- 

 tection. By skilful jugglings we are shown how anything and 

 everything may be rendered inconspicuous, usually by artificial 

 means, or under artificial conditions. The processes and steps by 

 which these phases of coloration have been reached are ignored. 

 The black and white skunk, the black and white zorilla of South 

 Africa, and the curious, badger-like Mydaus javanensis of Java 

 and Sumatra, have all independently taken on what we may call 

 skunk coloration, and have all developed the well-known skunk 

 smell. The line of demarcation between black and white as seen 

 against the sky-line by a cringing grasshopper, or some other sort 

 of puny prey, may in extremely rare cases aid the animal in getting 

 food ; but ordinarily speaking, the skunk would only be preyed on 

 from animals which swooped upon it from above; and the fact 

 that its insect prey surely has not eyes of the same image-forming 

 powers as our own makes us believe, as other naturalists have, 

 that this classic example of warning coloration is just as conspicu- 

 ous as we have always supposed it to be. 



Such creatures as Crows live by their wits, their wits are their 

 protection; and skill in escaping an enemy is surely a character 

 subject to evolution, and capable of considerable development. 

 We know that a savage sees a green parrot in a green tree almost 

 as easily as we see a hen strolling across a barnyard; and a hawk 

 sees a mouse running in the grass, while circling high in the air, 

 quite as easily. The hawk sees small birds in the same way; 

 and we believe that the bird which can dodge most skilfully is the 

 one that survives in the Ions: run. Cases of the extermination 



