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Pitcher plants are several different carnivorous plants which have modified leaves known as pitfall traps—a prey-trapping mechanism featuring a deep cavity filled with digestive fluid liquid. The traps of what we consider to be "true" pitcher plants are created from modified leaves, however they are not simply folded into a tube, the process is far more complicated. ==Types of pitcher plants== The term "pitcher plant" generally refers to members of the Nepenthaceae and Sarraceniaceae families, but similar pitfall traps are employed by the monotypic Cephalotaceae and some members of the Bromeliaceae. The families Nepenthaceae and Sarraceniaceae are the most species-rich families of pitcher plants. The Nepenthaceae contains a single genus, ''Nepenthes'', containing over 100 species and numerous hybrids and cultivars. In these Old World pitcher plants, the pitchers are borne at the end of tendrils that extend from the midrib of an otherwise unexceptional leaf. 'Old world' pitcher plants (genus: Nepenthes) are typically characterized as having reduced and symmetrical pitchers with a comprehensive waxy coating on the surface of the inner pitcher wall.〔Bauer, Ulrike, et al. "Form Follows Function: Morphological Diversification And Alternative Trapping Strategies In Carnivorous Nepenthes Pitcher Plants."Journal Of Evolutionary Biology 25.1 (2012): 90-102. MEDLINE with Full Text. 〕 The plants themselves are often climbers, accessing the canopy of their habitats using the aforementioned tendrils, although others are found on the ground in forest clearings, or as epiphytes on trees. The New World pitcher plants (Sarraceniaceae), which comprise three genera, are ground-dwelling herbs whose pitchers arise from a horizontal rhizome. In this family, the entire leaf forms the pitcher, as opposed to Nepenthaceae where the pitcher arises from the terminal portion of the leaf. The species of the genus ''Heliamphora'', which are popularly known as marsh pitchers (or erroneously as sun pitchers), have a simple rolled-leaf pitcher, at the tip of which is a spoon-like structure that secretes nectar. They are restricted to areas of high rainfall in South America. The North American genus ''Sarracenia'' are the trumpet pitchers, which have a more complex trap than ''Heliamphora'', with an operculum, which prevents excess accumulation of rainwater in most of the species. The single species in the Californian genus ''Darlingtonia'' is popularly known as the cobra plant, due to its possession of an inflated "lid" with elegant false-exits, and a forked "tongue", which serves to ferry ants and other prey to the entrance of the pitcher. The species in the genus ''Sarracenia'' readily hybridise, making their classification a complex matter. The Cephalotaceae is a monotypic family with but one genus and species, ''Cephalotus follicularis''. This species has a small (2–5 cm) pitcher similar in form to those of ''Nepenthes''. It occurs in only one location in southwestern Australia. A few species of bromeliads (Bromeliaceae), such as ''Brocchinia reducta'' and ''Catopsis berteroniana'', are known or suspected to be carnivorous. Bromeliads are monocots, and given that they all naturally collect water where their leaves meet each other, and that many collect detritus, it is not surprising that a few should have been naturally selected to develop the habit into carnivory by the addition of wax and downward-pointing hairs. The purple pitcher plant, ''Sarracenia purpurea'', is the floral emblem of the province of Newfoundland and Labrador, Canada. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「pitcher plant」の詳細全文を読む スポンサード リンク
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