No. 605] 



ANIMAL COLOFATION 



267 



Before conelndiiio- the disens^^ion of tliis matter it 

 should be stated tliat even if it wvvo ]»n)V('d Jhat bright- 

 colored insects are di vta-U'!'nl. it iiiiuiit not be infei'red 

 fairly that they are eoiispieiious, or that their coloration 

 lias a specific warning (aposematic) function. Feeding 

 experiments under ideal conditions might determine the 

 presence or absence of distastefulness, and show to what 

 extent it is correlated with the display of color combina- 

 tions of a particular sort. But even a high degree of 

 correlation between unpalatability and gaudy coloration 

 proves that the latter is conspicuous, no more than the 

 demonstration that an unknown substance has the ap- 

 proximate hardness of gold proves that it has the same 

 specific gravity; for brightness, or vividness of colora- 

 tion, and cons])ieuousness are incommensurable. 



Kxccpt in 'l'ha>('r's contributions, confusion upon this 

 p(»iMl lias prcxailcd from the beginning, when Wallace 

 used iiiterchangeal)ly the expressions, ''brilliantly colored 

 larva^" and "caterpillars conspicuous by their lively 

 coloration." But the assumption that some animals are 

 conspicuous, or, in other words, that while their habits 

 remain the same their average visibility might be greatly 

 diminished by another system of coloration than that 

 they possess, can neither be adequately defended nor re- 

 futed, until the results of such exhaustive studies of ani- 

 mals' habits as have rarely been attempted are available. 

 The distribution of animals must be studied intensively, 

 for the division of the world into provinces and the sub- 

 division of these into their major components by gross 

 dissection is not a technique of sufficient refinement to 

 discover the essential relations between organism and en- 

 vironment. 



Passing to another pliase of tlie matter, the value of 

 recorded observation- upon tlie eon-jticnousness of in- 

 sects may be shown \ cry clearly. 



Bates saw no Helieonida^ attacked by dragonflies or 



