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AROIDEAE (Arum family)
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See also:AROIDEAE (Arum See also:family) , a large and wide-spread botanical See also:order of Monocotyledons containing about moo See also:species in 105 genera. It is generally distributed in temperate and tropical regions, but especially See also:developed in warm countries. The See also:common See also:British representative of the order, Arum maculatum Fig.2. Arum maculatum, See also:Cuckoo-See also:pint. 1. Leaves and inflorescence. See also:succession (from below) See also:female 2. Underground See also:root-stock. See also:flowers, male flowers, and sterile 3. See also:Lower See also:part of spathe cut open. flowers forming a See also:ring of hairs 4. Spike of fruits. Showing in See also:borne on the spadix. (cuckoo-pint, lords and ladies, or See also:wake See also:robin), gives a meagre See also:idea of its development. The See also:plants are generally herbaceous, often, however, reaching a gigantic See also:size, but are sometimes shrubby, as in Pothos, a genus of shrubby climbing plants, chiefly Malayan. Monstera is a . tropical See also:American genus of climbing shrubs, with large often much-perforated leaves; the fruiting spikes of a Mexican species, M. deliciosa, are eaten. The roots of the climbing species are of See also:interest in their See also:adaptation
to the mode of See also:life of the plant. For instance, some species of Philodendron have a growth like that of See also:ivy, with feeding roots penetrating the See also:soil and clasping roots which See also:fix the plant to its support. In other species of the genus the See also:seed germinates on a See also:branch, and the seedling produces clasping roots, and roots which grow downwards See also:hanging like stout cords, and ultimately reaching the ground. The leaves, which show See also:great variety in size and See also:form, are generally broad and See also:net-veined, but in sweet-See also:flag (Acorns Calamus) are See also:long and narrow with parallel See also:veins. In Arum the blade is See also:simple, as also in the so-called arum-See also:lily (See also:Richardia), a See also:South See also:African species common in See also:Britain as a greenhouse plant, and in Caladium, a tropical South American genus, and Alocasia (tropical See also:Asia), species of which are favourite warm-greenhouse plants on See also:account of their variegated leaves. In other genera the leaves are much divided and sometimes very large; those of Dracontium (tropical See also:America) may be 15 it. high, with a long See also:stem-like stalk and a much-branched spreading blade. The See also:East See also:Indian genus Amorphophallus has a similar See also:habit. A See also:good See also:series of tropical aroids is to be seen in the aroid See also:house at See also:Kew. The so-called See also:water See also:cabbage (Pistia Stratiotes) is a floating plant widely distributed in the tropics, and consisting of rosettes of broadish leaves several inches across and a tuft of roots hanging in the water.
The small flowers are densely crowded on thick fleshy spikes, which are associated with, and often more or less enveloped by, a large See also:leaf (bract), the so-called spathe, which, as in cuckoo-pint, where it is See also:green in See also:colour, Richardia, where it is See also: The See also:fruit is a berry—the scarlet berries of the cuckoo-pint are See also:familiar See also:objects in the hedges in See also:late summer. The plants generally contain an acrid poisonous juice. The underground stems (rhizomes or tubers) are See also:rich in See also:starch; from that of Arum maculatum See also:Portland See also:arrowroot was formerly extensively prepared by pounding with water and then straining; the starch was deposited from the strained liquid. The order is represented in Britain by Arum maculatum, a See also:low herbaceous plant common in See also:woods and hedgerows in See also:England, but probably not See also:wild in See also:Scotland. It grows from a whitish root-stock which sends up in the See also:spring a few long-stalked, arrow-shaped leaves of a polished green, often marked with dark blotches. These are followed by the inflorescence, a fleshy spadix bearing in the lower part numerous closely crowded simple unisexual flowers and continued above into a purplish or yellowish appendage; the spadix is enveloped by a leafy spathe, constricted in the lower part to form a chamber, in which are the flowers. The mouth of this chamber is protected by a ring of hairs pointing downwards, which allow the entrance but prevent the See also:escape of small flies; after fertilization of the pistils the hairs See also:wither. The See also:insects visit the plant in large See also:numbers, attracted by the foetid See also:smell, and See also:act as See also:carriers of the See also:pollen from one spathe to another. .As the fruit ripens the spathe withers, and the brilliant red berries are exposed. The sweet-flag Acorns Calamus (q.v.), which occurs apparently wild in England in ditches, ponds, &c., is supposed to have been introduced. Additional information and CommentsThere are no comments yet for this article.
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