Figure 1.

Specular reflection and scattering spectra of (a,c,e) juvenile blue and (b,d,f) mature green S. willdenowii leaves. Intensity of specularly reflected light as a function of light incidence angle for (a) juvenile blue leaves and (b) mature green leaves (red line, θ₁ = 16°; black line, θ₁ = 22°; green line, θ₁ = 28°; blue line, θ₁ = 34°; light blue line, θ₁ = 40°; purple line, θ₁ = 46°; yellow line, θ₁ = 50°). (c,d) Enlargements of the reflection peaks in the blue and green spectral ranges from (a,b), respectively. Scattered intensity as a function of detection angle for a fixed light incidence angle of 36° for (e) juvenile blue leaves and (f) mature green leaves. The intensity is colour coded, with red (dark) corresponding to a lower intensity and yellow (bright) a higher intensity.