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1911 Encyclopædia Britannica/Moraceae

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MORACEAE, in botany, an order of dicotyledons, belonging to the series Urticiflorae, to which belongs also the nettle family (Urticaceae, q.v.). It contains about 60 genera with about 1000 species, mostly trees or shrubs, widely distributed in the warmer parts of the earth.

Fig (Ficus carica), Shoot bearing Leaves and Fruit.
1, Inflorescence cut lengthwise to show the numerous flowers crowded on the inner surface.
2, A female flower, enlarged. 3, Fruit cut lengthwise.

The largest genus, Ficus (the fig, q.v.), contains 600 species spread through tropical and sub-tropical regions, and includes the common fig of the Mediterranean region (Ficus carica), the banyan (F. bengalensis), and the india-rubber plant (F. elastica); many of the species are epiphytic, sometimes clinging so tightly round the host-plant with their roots as to strangle it. Morus (mulberry, q.v.) contains ten species of trees or bushes in north temperate regions and in the mountains of the tropics. Artocarpus, including A. incisa (bread-fruit, q.v.), and A. integrifolia (jack-tree), has forty species, chiefly natives in the Indian Archipelago. The plants are rich in latex which may be very poisonous as in Antiaris toxicaria, the Upas-tree (q.v.) of Java, or sweet and nutritious as in Brosimum galactodendron, the cow-tree (q.v.) of Venezuela. The latex often yields caoutchouc as in species of Ficus (e.g. F. elastica), Cecropia (q.v.), a tropical American genus with thirty to forty species, and others.

End of Shoot showing Stipule, s, of India-rubber Plant (Ficus elastica).

The leaves, which are entire or more or less divided, are stipulate, the stipules being small and lateral as in Morus and allied genera or intrapetiolar, each pair uniting to form a cap round the younger leaves, as in Ficus and allied genera, and very well shown in F. elastica, the common india-rubber plant of greenhouses. The plants are monoecious or dioecious, and the small unisexual flowers are borne in cymose inflorescences which are condensed into apparent racemes, spikes or heads. In the fig the coalesce to form a fleshy hollow axis on the inner face of which the flowers are situated, while in Dorstenia they form a flat, often lobed, expansion with the flowers sunk on the upper face.

Mulberry (Morus nigra), Shoot bearing Leaves and Fruit.
1, Catkin of male flowers.
2, One male flower.
3, Spike of female flowers.
4, Single female flowers.

The flower resembles that of Urticaceae; there are generally four free or more or less united perianth leaves, with, in the male flower, a stamen opposite each perianth leaf; the filaments are incurved in the mulberry and allied genera and straight in the fig and its allies. Artocarpus has only one stamen. The female flower contains two carpels in the median plane, the posterior one of which is often more or less aborted. Each developed ovary chamber contains a solitary pendulous more or less curved ovule. The fruit is an achene or drupe, often surrounded by the fleshy perianth and still further complicated by the union of fruits of different flowers as in mulberry, the development of a fleshy receptacle as in fig, or as in Artocarpus (bread-fruit), by the union o fruits, perianth and axis into a solid fleshy mass. The embryo is generally curved and surrounded by a fleshy endosperm.

From the evidence of leaf-fossils it is probable that the genus Ficus existed as far north as Greenland in the Cretaceous era and was generally distributed in North America and Europe in the Tertiary period up to miocene times.