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brand white in color and the lower half a light orange. The sex 
brand color does not change with death. 
The sex brand of Colias cesonia 
Colias cesonia males have a sex brand on the dorsal hindwing 
between the subcosta and radius veins near the wing base (Figure 
3D). The color of the brand ranges from lemon yellow to a light 
yellow with no consistent changes with age or death that we have 
observed. The color is solely attributible to the scales as the 
Figure 2. Scanning electron micrographs of N. iole wings. A-C, variation in the 
structure of sex brand scales; D, a scale from the discal cell; E, crude cross section 
through the sex brand showing pigment between the dorsal and ventral wing 
surfaces; F, crude cross section of the wings in the discal cell. See text for details. 
Scale lines: A-D, 20 /jl\ E and F, 5/j,. 
