Fig. 3. The eye of the small copper Lycaena phlaeas photographed from four
dorsal to ventral directions, differing by 30° from each other, with
broad-band, white light (halogen lamp) and monochromatic red (670nm) and green
(550nm) light. The effective aperture of the objective is approximately
60°. The frontal and ventral parts of the eye contain a mixture of red-
and yellow-green-reflecting ommatidia, but dorsally the reflection colours are
a mixture of blue and green; red reflection is absent from the dorsal region.
The central `hot spot' is due to reflection on the lens surfaces of the
microscope objective. 0° is approximately horizontal.
