262 



THE AMERICAN NATURALIST [Vol. LI 



live. It is this fact that necessitates a review of hypoth- 

 eses of animal coloration that postulate conspicnous- 

 ness; for one cannot safely disregard the suggestion that 

 principles applicable to one group of animals may be 

 valid also in the case of others. 



It is of interest to note that Chapman^ ^ studied the 

 birds of Trinidad under favorable conditions and ob- 

 served that distinct types of coloration marked those of 

 different habits. The most brilliant species occupy the 

 most exposed positions in the treetops. More sedentary 

 forms inhabiting the body of the trees are largely green, 

 and brown predominates in the coloring of those that 

 climb upon the tree-trunks, frequent the undergrowth near 

 the forest border, or live upon the forest bottom. 



These ecological records are a mere incident, a by- 

 product of their author's activity. Through lack of de- 

 tail they possess no great intrinsic value, but are highly 

 significant in their present setting. Mention should also 

 be made of Potts '^^ observation that shrimps living s}Tn- 

 biotically with crinoids upon the Australian reefs repeat 

 the colors of the forms with which they are associated. 

 That comparable facts regarding other groups of animals 

 are not available is immaterial. If the bright colors of 

 tropical birds, fishes and some Crustacea repeat those of 

 the animals' respective environments and minister to the 

 inconspicuousness of their possessors, it is of interest to 

 inquire what data and reasoning support the contention 

 that in insects similar combinations bear a different rela- 

 tion to the colors about them and discharge another func- 

 tion. 



It appears first, from the statements of a number of 

 their more prominent advocates, that there are funda- 

 mental theoretical objections to the hypotheses of warn- 

 ing coloration and mimicry. 



Poulton^*^ remarks that the acquisition of an unpleas- 

 ant taste or smell, together with a conspicuous appear- 



13 Bull. Amer. Mu^. Nat. Hist., Vol. 6, pp. 19-20. 



