290 



ZOOLOGY 



Warning 

 coloration 



Photograph by J. H. Watson 



FIG. 104. Grcdlsia Isabella on pine. This moth, which is found only in a limited 

 area in Spain, and is named after Queen Isabella, is of a delicate pea-green color, 

 the veins broadly covered with dark red scales. On the pine tree (Pinus maritima), 

 on which it feeds, its colors produce an effect similar to that of the pine needles. 



rests that it is extremely hard to detect it. Some moths 

 and caterpillars, however, are very conspicuous. Many 

 years ago the naturalist Bates wrote to Darwin, calling 

 his attention to an extremely gaudy tropical cater- 

 pillar of large size, ornamented with red, yellow, and 

 black. How can such colors be of any advantage, it 

 was asked ? Must they not betray the larvae to every 

 passing bird ? Darwin, puzzled, wrote to Wallace, who 

 suggested that perhaps the caterpillars were distaste- 

 ful to birds, and if so, the more easily they could be 

 recognized the better chance they would have of 

 avoiding the fatal experimental peck.' This has since 

 been shown to be really the case, and such examples 

 are classed under the head of warning coloration. Still 

 more remarkable are the resemblances between dif- 



