TATTERNS CONSPICUOUS IX NATURE. 407 



ipattern and the backgfound's pattern are blended, and provided 

 that both interrupt the junction of object and background, then 

 the blurring effect of these two interruptions are added, and 



'Cause the junction of object and background to appear much 

 more indistinct than when only one pattern interrupts. 



In text-fig. 16, if in each case the insects remain visible after 



•the patterns are blended, then the outline of the patterned one 

 will be the more indistinct when tlie tone of the patterned insect 



•after pattern-blending is the same as that of the plain insect. 



Text-fisfure 16. 





Visibility of insects on difFereiit backgrounds. 



It follows that animals with a pattern which interrupts the 

 ^m.argin will be less visible than plain animals against a patterned 

 background as well as against a plain one ; and further, that 

 -against a j)atterned background an uninterrupted margin will be 

 as necessary for conspicuousness as against plain backgrounds ; 

 in fact, experiments appeared to show that it was more necessary, 

 because the blurring effect of the background pattern required to 

 be counteracted. 



In Nature, a pattern which interrupts the margin must be a 

 .great aid to concealment against j)atterned backgrounds, because 

 the backgrounds are irregular and the animal must often be seen 

 with one or more of its margins against a single component of 

 the background, as shown in text-fig. 16. 



The conclusions as regards conspicuousness which have al- 

 j?eady been made must thus apply to patterned objects against 



27* 



