The natural history of plants, their forms, growth, reproduction, and distribution; (1895) (14577787879)

Identifier: cu31924011933227 (find matches) title: the natural history of plants, their forms, growth, reproduction, and distribution, half-volume 3, fig. 268, p. 255; year: 1895 (1890s) authors: kerner von marilaun, anton, 1831-1898 oliver, f. W. (francis wall), 1864-1951 busk, marian (balfour) lady, 1861-1941 macdonald, mary frances (ewart) kerner von marilaun, anton, 1831-1898. Pflanzenleben. English subjects: botany publisher: new york, h. Holt and company contributing library: cornell university library digitizing sponsor: msn view book page: book viewer about this book: catalog entry view all images: all images from book click here to view book online to see this illustration in context in a browseable online version of this book. Text appearing before image in the forms of the flowers and of their insect-visitors. A brief reference to two of the most striking modifications is all we can give here. The greatest variation is exhibited,as we said before, by the labellum and the rostellum. In some genera — in the twayblade (listera), for example — the part of the lip which contains the honey is not bowl-shaped, but in the form of a long, narrow furrow, and the secretion [page 255] removal of pollen in orchids. 255 is licked up by small beetles. In other instances the back of the lip is produced into a spur lined with cells full of sweet juice, to which insects obtain access by piercing the walls of the cells. The genus orchis affords an example of this. Honey of a sort peculiarly attractive to butterflies is secreted in the tubular spur in other cases, such as gymnadenia and habenaria (see fig. 258, p. 227). Two separate particles of viscid matter are often produced on the rostellum, each being in connection with one only of the pollen-masses (e. G. Habenaria text appearing after image fig, 268. — withdrawal and deposition of pollinia in the flowers of an orchid flowering spike of the broad-leaved helleborine (epipactis latifolia) upon which a wasp (vespa austriaca) is alighting. 2 a flower of the same seen from the front. 3 side view of the same flower with the half of the perianth towards the observer cut away. 4 the two pollinia joined by the sticky rostellum. 5 the same flower being visited by a wasp, which is licking honey and at the same time detaching with its forehead the tip of the rostellum together with the pair of pollinia. 6 the wasp leaving the flower with the pollinia cemented to its head; the pollinia are erect. 7 the wasp visiting another flower and pressing its forehead with the pollinia (which in the meantime have bent down) against the stigma. 1 nat. Size; the other figures x 2. Chlorantha, the large butterfly orchis). Insects then frequently only draw one of the pollen-masses out of the anther, instead of both, as they leave the flower. In species of. Date: 1895.