Page:EB1911 - Volume 25.djvu/372

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356
SOLANACEAE

a treaty formally placing Sokotra and its dependencies under the protection of Great Britain. Sokotra is regarded as a dependency of Aden, but native rule is maintained, the local governor or viceroy of the sultan of Kishin being a member of that chief’s family, and also styled sultan. Since it came under British control the islarfd has been visited by various scientific expeditions. Professor Bayley Balfour made an investigation in 1880, expeditions were headed by Drs Riebeck and Schweinfurth in 1881, by Theodore Bent in 1897, and by Dr H. O. Forbes and Mr Ogilvie-Grant (who also visited Abd-el-Kuri) in 1898–1899. Simultaneously with the last named a further expedition, conducted by Professor D. H. Müller, under the auspices of the Imperial Academy of Sciences of Vienna, visited Sokotra, Abd-el-Kuri and some other islets of the group to investigate their geology and languages. With the Indian government the relations of the Sokotri have occasionally been strained, owing to their piratical tendencies.

Abd-el-Kuri island lies 60 m. W.S.W. of Sokotra, and 53 m. E.N.E. from Cape Guardafui, is 20 m. long by 31/2 m. in width. At either end the island is hilly, the central part being a low plateau. On the north side is a sandy beach ; on the south, cliffs rise abruptly from the ocean. The highest part of the island is towards its eastern end, where the hills rise to 1670 ft. It is largely arid and there are no permanent streams. Its zoology resembles that of Sokotra, but the fauna includes land shells and scorpions peculiar to Abd-elr KurL The inhabitants, who number one to two hundred, speak Sokotri and Arabic and are chiefly engaged in diving for pearl shell on the Bacchus Bank N.E. of the island. They live chiefly on turtle (which abounds in the island), fish and molluscs. The land is nowhere cultivated.

Kal Farun is the name of two rocky islets rising nearly 300 ft. above the sea 13 m. N.N.E. of the western end of Abd-el-Kuri. Birds flock to them in great numbers; in consequence they are completely covered with guano, which gives them a snow-white appearance. The Brothers (often called by the older navigators The Sisters) lie between Abd-el-Kuri and Sokotra. Semha is 61/2 m. long and 3 m. broad. It has rocky shores and rises in a table-shaped mountain to 2440 ft. As in Abd-el-Kuri ambergris is found on its shores and turtles abound. There is running water all the year. It is a fishing ground of the Sokotri. Darzi lies 9 m. E. by S. of Semha, is 31/2 m. long by 1 m. broad and rises almost perpendicularly from the sea to 1500 ft. The top is flat. The coral banks which surround Sokotra and The Brothers are united and are not more than 30 fathoms below sea-level; a valley some 100 fathoms deep divides them from the bank around Abd-el-Kuri, while between Abd-el-Kuri and Cape Guardafui are depths of over 500 fathoms.

See, for the history of Sokotra, Yule, Marco Polo (1903 ed.) ii. 406–410, and, besides the authorities there cited, Yakut, s.v.; Hamdānī p. 52; Kazwini ii. 54. Consult also the Commentaries of Afonso Dalboquerque, W. de G. Birch’s translation (London 1875– 1884). For the state of the island at the beginning of the 18th century see the account of the French expedition to Yemen in 1708 (Viaggio new Arabia Felice: Venice, 1721); and, for the 19th century, J. R. Wellsted, City of the Caliphs, vol. il. (London, 1840), and Mrs J. T. Bent, Southern Arabia, Soudan and Sokotra (London, 1900). For the topography, &c, see Red Sea and Gulf of Aden Pilot (5th ed. London, 1900). For special studies see I. B. Balfour, Botany of Socotra (Edinburgh, 1888); G. Schweinfurth, Das Volk von Socotra (Leipzig, 1883) ; H. O. Forbes (edited by), The Natural History of Sokotra and Abd-el-Kūri (Liverpool, 1903); F. Kossmat, Geologic der Inseln Sokotra, Semha und Abd el Kuri (Vienna, 1902) ; R. V. Wettstein in Vegetationsbilder (3rd series, 5th pt., Jena, 1906). See also J. Jackson, Socotra, Notes bibliographies (Paris, 1892), a complete bibliography to the year of publication.  (H. O. F.; X.) 


SOLANACEAE, in botany, an order of Dicotyledons belonging to the sub-class Sympetalae (or Gamopetalae) and to the series Tubiflorae, containing 75 genera with about 1500 species, widely distributed through the tropics, but passing into the temperate zones. The chief centre of the order lies in Central and South America; 32 of the genera are endemic in this region. It is represented in Britain by three genera including 4 species: Hyoscyamus niger (henbane), Solanum Dulcamara (Bittersweet) and S. nigrum and Atropa Belladonna (Deadly Nightshade).

The plants are herbs, shrubs or small trees. Solanum nigrum, a common weed in waste places, is a low-growing annual herb; S. Dulcamara is an irregularly climbing herb perennial by means of a widely creeping rhizome; Atropa Belladonna is a large perennial herb. The genus Solanum, to which belong more than half the number of species in the order, contains plants of very various habits including besides herbs, shrubs and trees. The leaves are generally alternate, but in the flower-bearing parts of the stem are often in pairs, an arrangement which, like the extra-axillary position of the flowers or cymes, results from a congenital union of axes. Thus in Datura (thorn apple) (fig. 1 A), where the branching is dichasial, the leaf which originates at any given node becomes raised upon its axillary shoot as far as the next higher node, from which it appears to spring. In Atropa Belladonna (fig. 1 B) one of the branches at each node is undeveloped and there is a pair of unequal leaves; the smaller subtends the branch which has not developed, the larger has been carried up from the node below.

Fig. 1.—Diagrams illustrating branch development in Solanaceae, in A. Datura Stramonium, B. Atropa Belladonna.
Fig. 1.—Diagrams illustrating branch development in Solanaceae, in A. Datura Stramonium, B. Atropa Belladonna.

Fig. 1.—Diagrams illustrating branch development in Solanaceae, in A. Datura Stramonium, B. Atropa Belladonna.

I, II, III, Flowers on inflorescences of successive orders; b, bract of I; α, β, bracts of II; α′, β′, bracts of III, and so on. In A the branching is dichasial and the bracts are adnate to their axillary shoots up to the points at which the next branches arise ; thus α and β appear to arise from axis II, though in reality originating on axis I. In B the branching is. cincinnal, one of the two branches at each node is undeveloped and its, bract α, α′, α″ is smaller than the other member of the pair, β, β′, which is adnate to and apparently carried up on its axillary branch.

An interesting anatomical feature is the presence in the stem of bicollateral bundles—that is, the vascular bundles have phloem on the inside as well as on the outside of the xylem.

The hermaphrodite, generally regular, flowers have the parts in fives, 5 sepals, 5 petals, 5 stamens in alternating whorls, and two carpels, which are generally placed obliquely (see fig. 2, floral diagram).

Fig. 2.—Floral diagram of Solanum—the arrow indicates the oblique symmetry of the flower.
Fig. 2.—Floral diagram of Solanum—the arrow indicates the oblique symmetry of the flower.
Fig. 3.—Floral diagram of Schizanthus—the arrow indicates the oblique symmetry. Two stamens only are functional.
Fig. 3.—Floral diagram of Schizanthus—the arrow indicates the oblique symmetry. Two stamens only are functional.
Fig. 2.—Floral diagram of Solanum—the arrow indicates the oblique symmetry of the flower. Fig. 3.—Floral diagram of Schizanthus—the arrow indicates the oblique symmetry. Two stamens only are functional.

The sepals persist and often become enlarged in the fruit. The corolla is regular and rotate as in Solanum (fig. 2), or bell-shaped as in Atropa, or somewhat irregular as in Hyoscyamus; in the tribe Salpiglossideae, which forms a link with the closely allied order Scrophulariaceae, it is zygomorphic, forming, e.g. as in Schizanthus (fig. 3), a two-lipped flower. The stamens are inserted on the corolla tube and alternate with its lobes; in zygomorphic flowers only two or four fertile stamens are present; the bilocular anthers open by slits or pores (fig. 4).


Fig. 4.—Stamen of a species of Solanum, showing the divergence of the anther-lobes at the base, and the dehiscence by pores at the apex a.

The flowers are generally conspicuous and adapted to insect pollination; honey is secreted on the disk at the base of the ovary or at the bottom of the corolla tube between the stamens. The ovary is usually bilocular, but in Capsicum becomes unilocular above, while in some cases an in-growth of a secondary septum makes it 4-celled as in Datura, or irregularly 3- to 5-celled as in Nicandra. The anatropous ovules are generally numerous on swollen axile placentas, sometimes few as in Cestrum, a large American geflus with tubular flowers, species of which are grown in Britain as greenhouse plants; the simple style bears a bilobed or sometimes capitate stigma (fig. 5). The fruit is a many-seeded berry, as in Solanum, or