Cattleya Orchid and Three Hummingbirds 1870s. The NGA describes the work: "Lichen covers dead branches; moss drips from trees; and, a blue-gray mist veils the distant jungle. An opulent pink orchid with light-green stems and pods dominates the left foreground." On the right, two green-and-pink Brazilian Amethysts hover about a nest while a red-tailed Sappho Comet perches nearby. Cattleya Orchid and Three Hummingbirds Cattleya Orchid and Three Hummingbirds (1871) is an oil on mahogany panel picture by Martin Johnson Heade acquired by the National Gallery of Art in 1982. Inspired perhaps by the works of Charles Darwin and Frederic Edwin Church, Heade planned to produce
Basics of blue flower colouration Basics of blue flower colouration Blue flower colour was always associated with something unusual and desired. Blue roses especially were assumed to be a dream that cannot be realised. Blue colour in flower petals is caused by anthocyanins, which are members of flavonoid class metabolites. We can diversify three main classes of anthocyanin pigments: cyaniding type (two hydroxyl groups in the B-ring) responsible for red coloration, pelargonidin type (one hydroxyl group in the B-ring) responsible for orange colour and delphinidin type (three hydroxyl groups in the B-ring) responsible for violet/blue flower and fruits coloration. The main difference in the structure