EUPHORBIACEAE , inbotany, a large natural
See also:order of flowering
See also:plants, containing more than 220 genera with about ' See Dr Schafhf.utl's article on Musical
See also:Instruments " in
See also:sect. iv . Of Bericht der Beurtheilungs- Commission
See also:ben der Allg. deutschen Industrie Ausstellung (
See also:Munich, 1854), pp . 169-170; also Fried . Zamminer, Die Musik and die Musikinstrumente in ihrer Beziehung zu den Gesetzen der Akustik (
See also:Giessen, 1855) . 4000
See also:species, chiefly tropical, but spreading over the whole
See also:earth with the exception of the arctic and
See also:cold alpine zones . They are represented in Britain by the spurges (
See also:Euphorbia, q.v.) (fig.') and
See also:dog's mercury (Mercurialis) (fig . 2), which are herba- ceous plants, but the greater number are woody plants and often trees . The large genus Euphorbia shows
See also:great variety in
See also:habit; many species, like the
See also:English spurges, are
See also:annual herbs, others
See also:form bushes, while in the
See also:desert regions of tropical Africa and the Canary Islands species occur re- 893 unisexual, the male often containing numerous
See also:flowers while the
See also:female flowers are solitary . The partial inflorescence (cyathium) of Euphorbia (fig. i) resembles superficially a hermaphrodite flower . - It contains a central terminal flower, consisting of a naked
See also:pistil; below this are
See also:borne four or five bracts which unite to form a
See also:cup-shaped involucre resembling a calyx; each of these bracts subtends a small cyme of male flowers each consisting only of one stamen . Between the segments of the cup are large
See also:oval or
See also:crescent-shaped glands which. are often brightly coloured, forming petal-like structures . The form of the flower shows great variety .
See also:complete type occurs in Wielandia, a
See also:shrub from the
See also:Seychelles Islands, in which the flowers have their parts in
See also:fives, a calyx and corolla being succeeded in the male flower by 5 stamens, in the female by 5 carpels . Generally, however, only 3 carpels are
See also:present, as in Euphorbia; Mercurialis (fig . 2) has minute apetalous flowers with 3 sepals, followed in the male by 8 to 20 stamens, in the female by a bicarpellary pistil . In the large tropical genus Croton a pentamerous calyx and corolla are generally present, the stamens are often very numerous, and the female flower has three carpels . In Manihot, a large tropical
See also:American genus to which belongs the manioc or
See also:cassava (M. utilissima), the calyx is often large and petaloid . In a great many genera the corolla is absent . The most reduced type of flower is that 4 . 5 . I . Shoot of Euphorbia hypericifolia, about z nat.
See also:size . 2 . A partial inflorescence, cyathium, bearing the petaloid glands .
3 . A similar one at a laterstage, cut open to show the singlestamened (monandrous)male flowers and the central long-stalked female flower . A cyathium without petaloid glandular appendages . A similar one at a later stage with nearly ripe fruit . 6 . An anther dehiscing . 7 . Fruit dehiscing and exposing one of the three seeds, I . 8 . Seed . 9 . Seed cut lengthwise exposing the embryo .
See also:Diagram of the inflorescence of Euphorbia, illustrating the dichasial' cymose arrangement of the ultimate branches . b, Bract subtending the central terminal cyathium I . a' b', Bracteoles of the first order subtending the secondary cyathia II . a" b", Bracteoles of the second order subtending the
See also:tertiary cyathia III . In the central cyathium I. are shown, the details of, the arrangement of the male flowers in monochasial cymes, m, and the central female flower, f . sembling cacti, having thick fleshy stems and leaves reduced to spines . Another large genus, Phyllanthus, contains small annual herbs as well as trees, while in some species the leaves are reduced to scales, and the branches are flattened, forming phylloclades . The leaves also show great variety in form and arrangement, being
See also:simple and entire as in the English spurges, or deeply cut as in Ricinus (
See also:castor-oil) (fig .. 3), and Manihot or sometimes palmately compound (Hevea) . The majority contain a milky juice or latex in their tissues which exudes on cutting or bruising . In Hevea, Manihot and others the latex yields caoutchouc .
The flowers are unisexual; male and female flowers are borne on the same, as in the spurges (fig . I), or on different plants, as in dog's mercury (fig . 2) . Their arrangement shows considerable variation, but the flowers are generally grouped in crowded definite partial inflorescences, which are themselves arranged in spikes or stand in the axils of the upper leaves . These partial inflorescences are generally I . Male plant . 5 . Fruit beginning to split open . 2 . Female plant ; t nat. size . 6 . Seed cut lengthwise showing 3 .
Female flower. the embryo . ¢ . Male flower, described in EUPBORI3IA, where the male consists of one stamen separated from its pedicel by ajoint, and the female of a naked tricarpellary pistil . The stamens are sometimes more or less
See also:united . (monadelphous), and in castor-oil (Ricinus) (fig . 3) are much branched . The ovary generally contains threg
See also:chambers, and bears three simple or more often bipartite styles; each chamber contains one or two pendulous ovules, which generally bear a cap-like outgrowth or caruncle, which persists in the seed (well shown in castor oil, fig . 3) . As the stamens and pistil are borne by different flowers,
See also:cross-fertilization is necessary . In Mercurialis and others with inconspicuous flowers
See also:pollination is effected by the
See also:wind, but in many cases
See also:insects are attracted to the flower by the highly-coloured bracts, as in many Euphorbias and Dalechampia, or by the coloured calyx as in Manihot; the presence of
See also:honey is also frequently an attraction, as in the honey-glands on the bracts of the cyathium of Euphorbia . The fruit is generally a capsule which splits into three divisions (cocci), separating from the central
See also:column, and splitting lengthwise into two valves . In the mancinil (Ilippomane mancinella) of Central
See also:America the fruit is a drupe like a
See also:plum, and in some genera berries occur .
In the sandbox
See also:tree (Hura crepitans) of tropical America the ovary consists of numerous carpels, and forms when mature a capsule which splits with great violence and a loud
See also:report into a number of woody cocci . The seeds contain abundant endosperm and a large straight or bent embryo . Several members of the order are of economic importance . From Bentley and Trimen's Medicinal Plants, by permission of J . & A .
See also:Churchill . 1 . Section of male flower, about 4 . Seed . nat. size . 5 and 6 . Vertical and transverse 2 .
See also:Group of stamens sections of seed showing 3 . Fruit. embryo in position . Manihot utilissima, manioc or cassava (q.v.), is one of the most important tropical
See also:food-plants, its thick tuberous
See also:root being
See also:rich in
See also:starch; it is the source of Brazilian
See also:arrowroot . Caoutchouc or india-
See also:rubber is obtained from species of Hevea, Mabea, Manihot and Sapium . • Castor oil (q.v.) is obtained from the seeds of Ricinus communis . The seeds of Aleurites moluccana and Sapium sebiferum also yield oil .
See also:Resin is obtained from species of Croton and Euphorbia . Many of the species are poisonous; e.g. the South
See also:African Toxicodendron is one of the most poisonous plants known . Many, such as Euphorbia, Mercurialis, Croton, Jatropha, Tragic, have been, or still are, used as medicines . Species of
See also:Codiaeum (q.v.), Croton, Euphorbia, Phyllanthus, Jatropha and others are used as ornamental plants in gardens . The box (Buxus) and a few allied genera which were formerly included in Euphorbiaceae are now generally regarded as forming a distinct order—Buxaceae, differing from Euphorbiaceae in the position of the ovule in the ovary-chamber and in the manner of splitting of the fruit .
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