THE APPARENT DISRUPTION OF SURFACE. 



255 



of concealment. It may be said with confidence, that the whole 

 of the Geometers in respect of the dorsal surface of their wings, of 

 the ISToctuas with regard to the dorsal surface of their anterior- 

 wings, and of the Rhopalocera in respect of the ventral surface of 

 their posterior wings, present concealing pattern and coloration. 

 Here, therefore, " Surface Disruption by Contrast " may be 

 looked for. 



Text-figure 2. 

 A B CD 



A^a pattern similar to that shown in text-fig. 1, but with the addition of Surface 

 Disruption produced by light and dark lines between the components ; 

 in C the surface is further disrupted by the representation of solidity. 

 B shows " Surface Disruption by Contrast " not associated with disruption 

 of outline. This is i-arely found : Thyatira hatis is a good example. 

 D shows the combination of Surface Disruption by Contrast with Surface 

 Disruption by Solidit}'. Large ocelli generally appear to be of this nature. 



Shows in diagram seven types of pattern commonly found in Geometers and other 

 Lepidoptera, in which Surface Disruption by Contrast is combined with 

 Outline Disruption. Many variations occur of type no. 6 ; in some cases the 

 bands are wavy or zigzag, more especially in the fore wings of Noctuidae. 



An examination of the Geometridje (Newman) shows that 

 surface disruption occurs, associated with well-marked types of 

 outline disruption. These are illustrated diagrammatically in 

 text-fig. 3, and are seen to consist of well-defined bars of tone 

 interrupting the margin and which are separated from the rest of 



