The Reflection of Ultraviolet by Flowers

Effects of Epidermal Cell Shape and Pigmentation on Optical Properties of Antirrhinum Petals at Visible and Ultraviolet Wavelengths

“…UV-absorption patterns, although invisible to humans, are perceived by bees, which are most sensitive to wavelengths in the UV-A through yellow spectral regions (Kevan, 1983). These patterns were documented photographically, and a role for UV-absorption patterns, as cues for pollinator orientation, was proposed more than 70 years ago (Richtmyer, 1923;Lutz, 1924).…”

Ecological Photometry and a New Instrument for Measuring Light

“…cit.,p. 250), and the region (ultra-violet) which produces "sunburn" and "tanning" of the skin (Woodruff, 1905;Hill & Eidenow, 1923) and forms part of the visible spectrum of many insects (Kiihn and Pohl, 1921;Richtmyer, 1923;Lutz, 1924).…”

Anthochlor Pigments and Pollination Biology. I. The UV Absorption of Antirrhinum majus Flowers

“…The existence of UV-absorbing, floral pigmentation patterns invisible to the human eye, but visible to insect pollinators, was photographically documented early in this century ( Richtmyer, 1923;Lutz, 1924). Identification of the chemical compounds responsible for producing these patterns was accomplished only recently when Thompson et al ( 1972) demonstrated that flavonol glycosides produced the floral UV-absorption pattern present in Rudbeckia hirta L. Those workers noted ( their footnote 16) that the anthochlor pigments ( aurones and chalcones) also possess absorption maxima appropriate for participation in floral UV-absorption phenomena.…”