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SCROPHULARIACEAE

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Originally appearing in Volume V24, Page 486 of the 1911 Encyclopedia Britannica.
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SCROPHULARIACEAE , in See also:

botany, a natural See also:order of See also:seed-See also:plants belonging to the sympetalous See also:section of See also:Dicotyledons, and a member of the See also:series Tubiflorae. It is a See also:cosmopolitan order containing about 18o genera with about 2000 See also:species; the See also:majority occur in temperate regions, the See also:numbers diminishing rapidly towards the tropics and colder regions. About 30% of the species are See also:annual herbs, such as eyebright (Euphrasia officinalis), cow-See also:wheat (Melampyrum), and species of See also:Veronica` Fio. 1.—See also:Foxglove (See also:Digitalis purpurea). 1, Corolla cut open showing the showing the thick axial four stamens, rather more See also:placenta bearing numerous than Z nat. See also:size small seeds. 2, Unripe See also:fruit cut lengthwise, 3, Ripe See also:capsule split open. more than 6o% are biennial or generally perennial herbs and undershrubs, such as species of Veronica, mullein (Verbascum), foxglove (Digitalis; fig. 1), &c., while shrubs and trees are rare; Paulownia, a native of the mountains of See also:Japan, a See also:tree with large leaves and handsome panicles of See also:violet See also:flowers, is grown in See also:European gardens. The See also:stem is sometimes prostrate and creeping, as in See also:ivy-leaved See also:toad-See also:flax (Linaria Cymbalaria) and some of the native See also:British Veronicas, but generally erect as in foxglove, figwort, mullein, &c.; a few are climbers as Rhodochiton and Maurandia. The See also:South See also:African genera Hyobanche and Harveya are parasites almost devoid of See also:chlorophyll with See also:scale-like leaves; and many genera are semiparasitic, having See also:green leaves, but attaching themselves by See also:root-suckers to roots of grass, &c., from which they derive See also:part of their nourishment; such are Euphrasia, Rhinanthus, Pedicularis, &c. A few genera are aquatic, e.g. Ambulia (old See also:world tropics), and have much Scrophulariaceae are closely allied to See also:Solanaceae (q.v.), from which divided submerged leaves and entire aerial leaves.

The See also:

leaf-arrange- they are distinguished by the median position of the carpels, and ment varies; the leaves are alternate as in Verbascum, or the See also:lower generally by the zygomorphic See also:flower; Verbascum and its See also:allies, in leaves are opposite and the upper alternate as in Antirrhinum (snap- See also:dragon), or all are opposite (See also:Mimulus), or whorled (some Veronicas). All varieties of leaf-arrangement are found in the one genus Veronica (q.v.), in some New See also:Zealand species of which the leaves are small and appressed to the stem. The flowers are solitary in the leaf-axils, as in Mimulus, species of Linaria, &c., or See also:form spikes or racemes which are terminal as in foxglove, species of Veronica, &c., or axillary as in Veronica (Chamaedrys section). Cymose inflorescences also occur, as in Verbascum, consisting of dichasia arranged in spikes, racemes or panicles. The flowers are hermaphrodite, hypogynous and zygomorphic in the median See also:plane, being often more or less two-lipped, and having five sepals joined below and persisting in the fruiting See also:stage five petals uniting to form a corolla of very various shape, generally four stamens, the fifth (posterior) being suppressed or represented by a rudiment, while the anterior pair are longer than the posterior, and two generally equal carpels in the median plane forming a two-celled ovary containing numerous anatropous ovules on a thick See also:axile placenta, and bearing a See also:simple or bilobed See also:style (fig. 2). which the flower approaches regularity, form a connecting See also:link. b, Veronica. c, Verbascum. When a terminal flower is See also:present it becomes See also:regular as in toad-flax, where radial symmetry is produced by development of a See also:spur to each petal—such flowers are termed peloric; all the flowers in a spike are sometimes peloric. In Euphrasia and many species of Veronica the posterior sepal is suppressed, and in See also:Calceolaria the anterior petals are completely See also:united. The form of the corolla shows See also:great variety, depending on the length and breadth of the See also:tube—which in Veronica is almost obsolete, while in foxglove it is large and almost See also:bell-shaped—and the development of the limbs, which are spreading in Veronica, small and almost erect in figwort, or form a pair of closed lips as in Linaria and Antirrhinum. In Linaria the anterior petal is spurred; in Calceolaria a very See also:short tube is succeeded by a two-lipped See also:limb, a smaller upper See also:lip representing the two posterior petals and a larger, often very large, lower lip representing the three anterior petals.

In Verbascum the five segments are almost equal, forming a nearly regular corolla; in Veronica the two posterior petals have united and the corolla is four-lobed. The approach to regularity in the corolla in Verbascum is associated with the presence of five fertile stamens, but the three posterior are generally larger than the two anterior. In Veronica, Calceolaria and other genera only two stamens are present. The anthers generally open introrsely by a See also:

longitudinal slit; their form shows great variety. These See also:differences in the form of the corolla, the position and length of the stamens and the form of the anthers, are associated with their See also:pollination by See also:insects which probe the flower for See also:honey, which is secreted by a disk surrounding the See also:base of the ovary or by See also:special nectaries below it. Verbascum and Veronica with a short-tubed corolla represent an open type of flower with more exposed See also:nectar; in foxglove the honey is at the base of the See also:long tube, and a See also:bee crawling to reach it will rub with its back the anthers or stigmas which are placed on the upper See also:side of the bell. The closed flowers of Linaria and Antirrhinum can be visited only by insects which are strong enough to See also:separate the lips. In Euphrasia and others the See also:pollen is loose and powdery, and the anthers have appendages which when touched by the See also:head of the See also:insect-visitor cause the pollen to be scattered. The fruit is generally a capsule surrounded at the base, or some-times as in yellow-rattle (Rhinanthus) enveloped in the persistent calyx; it opens by two or four valves, or, as in Antirrhinum, by pores. Occasionally it is a See also:berry. The seeds are generally small and numerous, rarely few and large as in Veronica. In Linaria Cymbal-See also:aria the fruit becomes buried by the stalks bending downwards when ripe.

The order is divided into tribes by characters derived from the number of fertile stamens present and the form of the corolla. It is well represented in See also:

Britain by 13 genera, viz. Verbascum (mullein), Linaria (toad-flax), Antirrhinum (See also:snapdragon), Scrophularia (fig-wort), Limosella—a small creeping annual found on edges of ponds, Siblhorpia, a small See also:herb with creeping See also:thread-like stems, Digitalis (foxglove), Veronica (speedwell), Bartsia, Euphrasia (eyebright), Rhinanthus (yellow-rattle), Pedicularis (See also:louse-wort) and Melampyrum (cow-wheat). An See also:American species of Mimulus (M. Langsdorfii) has become naturalized by See also:river-sides in many places. Several genera are well known in gardens; such are Calceolaria, an important genus in temperate South See also:America, Collinsia, See also:Pentstemon and Mimulus (See also:musk), also American genera. An anatomical, distinction is found in the arrangement of the See also:wood and bast in the stem, which is See also:collateral, not bicollateral as in Solanaceae. SCRUB-See also:BIRD, the name of an Australian genus, one of the most curious ornithological types of the many furnished by that See also:country. The first examples were procured between See also:Perth and See also:Augusta in See also:West See also:Australia, and were described by J. See also:Gould in the Zoological Society's Proceedings for 1844 (pp. I, 2) as forming a new genus and species under the name of Atrichia clamosa, the great peculiarity observed by that naturalist being the See also:absence of any bristles around the gape, in which respect alone it seemed to differ from the already known genus Sphenura. Later, however; it was given its See also:modern name Atrichornis clamosa, and on See also:account of the See also:discovery of its See also:peculiar sternum (made by A.

See also:

Newton) it was removed from Oscine See also:division of the Passeres, and the See also:family Atrichornithidae in the sub-oscine division of Passeres was made for the genus, the nearest ally West-Australian Scrub-bird (Atrichornis clamosa). being the See also:lyre-bird (q.v.), now placed in the family Menuridae. Both the known species of scrub-bird are about the size of a small See also:thrush—A. clamosa being the larger of the two. This species is See also:brown above, each See also:feather barred with a darker shade; the See also:throat and belly are reddish See also:white, and there is a large See also:black patch on the See also:breast; while the flanks are brown and the lower tail-coverts rufous. A. rufescens of New South See also:Wales has the white and black of the fore-parts replaced by brown, barred much as is the upper plumage. Both species inhabit the thickest " scrub " or brushwood See also:forest; but little has been ascertained as to their mode of See also:life except that the See also:males are noisy, imitative of the notes of other birds, and given to violent gesticulations. The See also:nest and eggs seem never to have been found, and indeed no example of the See also:female of either species is known to have been procured, whence that See also:sex may be inferred to See also:escape observation by its inconspicuous See also:appearance and retiring habits. (A.

End of Article: SCROPHULARIACEAE

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