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W. L. G.

W. M.

W. M. F. P.

W. O. B.

W. R. M.

W. R. S.

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WILLIAM MINTO, M.A., LL.D.

See the biographical article: MINTO, WILLIAM.

WILLIAM MATTHEW FLINDERS PETRIE, F.R.S., D.C.L., LITT.D.
See the biographical article: PETRIE, W. M. F.

VEN. WINFRID Oldfield Burrows, M.A.

Archdeacon of Birmingham. Student and Tutor of Christ Church, Oxford, 1884

Prince Edward Island;
Quebec: Province (in part);
Quebec: City.

{Pope, Alexander (in part).
{Pyramid.

1891. Principal of Leeds Clergy School, 1891-1900. Author of The Mystery of the Prayers for the Dead.

Cross.

WILLIAM RICHARD MORFILL, M.A. (d. 1910).

Formerly Professor of Russian and the other Slavonic Languages in the University Pushkin.
of Oxford. Curator of the Taylorian Institution, Oxford. Author of Russia;
Slavonic Literature; &c.

WILLIAM ROBERTSON SMITH, LL.D.

See the biographical article: SMITH, WILLIAM Robertson.

Priest (in part);

Prophet (in part);

Psalms, Book of (in part);
Rameses (in part).

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Minister, Higher Broughton Presbyterian Church, Manchester, 1877-1901, and Presbyterianism.
Association Secretary for the Religious Tract Society in the North of England.

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ENCYCLOPÆDIA BRITANNICA

ELEVENTH EDITION

VOLUME XXII

cesses.

POLL, strictly the head, in men or animals. Skeat connects | of brutality, of which the characteristics can be studied in the the word with O. Swed. kolle (initial p and k being interchange- "Saint Sebastian," painted in 1475, and now in the National able) and considers a Celtic origin probable; cf. Irish coll, Welsh col, peak, summit. "Poll" is chiefly used in various senses derived from that of a unit in an enumeration of persons or things, e.g. poll-tax (q.v.), or “challenge to the polls" in the case of a jury (q.v.). The most familiar derivative uses are those connected with voting at parliamentary or other elections; thus "to poll" is to vote or to secure a number of votes, and "the poll," the voting, the number of votes cast, or the time during which voting takes place. The verb "to poll" also means to clip or shear the top of anything, hence "polled" of hornless cattle, or "deed-poll" (i.e. a deed with smooth or unindented edges, as distinguished from an "indenture"). A tree which has been "polled," or cut back close in order to induce it to make short bushy growth, is called a "pollard." At the university of Cambridge, a "pass" degree is known as a " poll-degree.' This is generally explained as from the Greek of rooi, the many, the common people.

POLLACK (Gadus pollachius), a fish of the family Gadidae, abundant on rocky coasts of northern Europe, and extending as far south as the western parts of the Mediterranean, where, however, it is much scarcer and does not attain to the same size as in its real northern home. In Scotland and some parts of Ireland it is called lythe. It is distinguished from other species of the genus Gadus by its long pointed snout, which is twice as long as the eye, with projecting lower jaw, and without a barbel at the chin. The vent is below the anterior half of the first dorsal fin. A black spot above the base of the pectoral fin is another distinguishing mark. Although pollack are wellflavoured fish, and smaller individuals (from 12 to 16 in.) excellent eating, they do not form any considerable article of trade, and are not preserved, the majority being consumed by the captors. Specimens of 12 tb are common, but the species is said to attain occasionally as much as 24 tb in weight. (See also COALFISH.)

POLLAIUOLO, the popular name of the brothers Antonio and Piero di Jacobo Benci, Florentines who contributed much to Italian art in the 15th century. They were called Pollaiuolo because their father was a poulterer. The nickname was also extended to Simone, the nephew of Antonio.

ANTONIO (1429-1498) distinguished himself as a sculptor, jeweller, painter and engraver, and did valuable service in perfecting the art of enamelling. His painting exhibits an excess

Gallery, London. A "St Christopher and the Infant Christ " is in the Metropolitan Museum, New York. But it was as a sculptor and metal-worker that he achieved his greatest suc The exact ascription of his works is doubtful, as his brother Piero did much in collaboration with him. The museum of Florence contains the bronze group "Hercules strangling Cacus" and the terra-cotta bust "The Young Warrior "; and in the South Kensington Museum, London, is a bas-relief representing a contest between naked men. In 1489 Antonio took up his residence in Rome, where he executed the tomb of Sixtus IV. (1493), a composition in which he again manifested the quality of exaggeration in the anatomical features of the figures. In 1496 he went to Florence in order to put the finishing touches to the work already begun in the sacristy of Santo Spirito. He died in 1498, having just finished his mausoleum of Innocent VIII., and was buried in the church of San Pietro in Vincula, where a monument was raised to him near that of his brother.

PIERO (1443-1496) was a painter, and his principal works were his "Coronation of the Virgin," an altar-piece painted in 1483, in the choir of the cathedral at San Gimignano; his "Three Saints," an altar-piece, and "Prudence are both at the Uffizi Gallery.

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SIMONE (1457-1508), nephew of Antonio Pollaiuolo, a celebrated architect, was born in Florence and went to Rome in 1484; there he entered his uncle's studio and studied architecture. On his return to Florence he was entrusted with the completion of the Strozzi palace begun by Benedetto de Maiano, and the cornice on the façade has earned him lasting fame. His highly coloured accounts of Rome earned for him the nickname of il Cronaca (chronicler). About 1498 he built the church of San Francesco at Monte and the vestibule of the sacristy of Santo Spirito. In collaboration with Guiliano da Sangallo he designed the great hall in the Palazzo Vecchio. He was a close friend and adherent of Savonarola.

See also Maud Cruttwell, Antonio Pollaiuolo (1907).

POLLAN (Coregonus pollan), the name given to a species of the Salmonoid genus Coregonus (whitefish) which has been found in the large and deep loughs of Ireland only. A full account of the fish by its first describer, W. Thompson, may be found in his Natural History of Ireland, iv. 168.

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POLLARD,

EDWARD ALBERT (1828-1872), American | pointed out by Sprengel, may be so well marked that the stigma has ceased to be receptive before the anthers open, or the anthers have withered before the stigma becomes receptive, when crosspollination only is possible, or the stages of maturity in the two organs are not so distinct, when self-pollination becomes possible later on. The flower is termed proterandrous or proterogynous according as anthers or stigmas mature first. The term homogamy is applied to the simultaneous maturity of stigma and anthers. Spontaneous self-pollination is rendered impossible in some homogamous flowers in consequence of the relative position of the anthers and stigma-this condition has been termed herkogamy. Flowers in which the relative position of the organs allows of spontaneous self-pollination may be all alike as regards length of style and stamens (homomorphy or homostyly), or differ in this respect (heteromorphy) the styles

journalist, was born in Nelson county, Virginia, on the 27th of February 1828. He graduated at the university of Virginia in 1849, studied law at the College of William and Mary, and in Baltimore (where he was admitted to the bar), and was engaged in newspaper work in California until 1855. In 1857-1861 he was clerk of the judiciary committee of the National House of Representatives. By 1859 he had become an outspoken Secessionist, and during the Civil War he was one of the principal editors of the Richmond Examiner, which supported the Confederacy but was hostile to President Jefferson Davis. In 1864 Pollard sailed for England, but the vessel on which he sailed was captured as a blockade runner, and he was confined in Fort Warren in Boston Harbour from the 29th of May until the 12th of August, when he was paroled. In December he was placed in close confinement at Fort Monroe by order of Secretary Stanton, but was soon again paroled by General B. F. Butler, and in January proceeded to Richmond to be exchanged there for Albert D. Richardson (1833-1869), a well-known correspondent of the New York Tribune, who, however, had escaped before Pollard arrived. In 1867-1869 Pollard edited a weekly paper at Richmond, and he conducted the Political Pamphlet there during the presidential campaign of 1868.

His publications include Black Diamonds Gathered in the Darkey Homes of the South (1859), in which he advocated a reopening of the slave trade; The Southern History of the War (3 vols.: First Year of the War, with B. M. DeWitt, 1862; Second Year of the War, 1864: Third Year of the War, 1864); Observations in the North: Eight Months in Prison and on Parole (1865); The Lost Cause (1866); Lee and His Lieutenants (1867); The Lost Cause Regained (1868), a southern view of reconstruction urging the necessity of white supremacy; The Life of Jefferson Davis (1869), an arraignment of the Confederate president; and The Virginia Tourist (1870).

POLLENTIA (mod. Pollenzo), an ancient town of Liguria, Italy, 10 m. to the north of Augusta Bagiennorum, on the left bank of the Tanarus (mod. Tanaro). Its position on the road from Augusta Taurinorum to the coast at Vada Sabatia, at the point of divergence of a road to Hasta (Asti) gave it military importance. Decimus Brutus managed to occupy it an hour before Mark Antony in 43 B.C.; and it was here that Stilicho on the 29th of March 403 fought the battle with Alaric which though undecided led the Goths to evacuate Italy. The place was famous for its brown wool, and for its pottery. Considerable remains of ancient buildings, an amphitheatre, a theatre and a temple still exist. The so-called temple of Diana is more probably a tomb.

See G. Franchi-Pont in Atti dell' accademia di Tornio (18051808), p. 321 sqq.

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K

G

(From Strasburger's Lehrbuch der Botanik, by permission of Gustav Fischer.)
FIG. 1.-Long-styled, L, and short-styled, K, flowers of Primula
sinensis.

G, Level of stigma; S, level of anthers; P, N, pollen grains and
stigmatic papillae of long-styled form; p, n, ditto of short-styled form.
and stamens being of different lengths in different flowers
(heterostyly) or the stamens only are of different lengths (heter-
anthery). Flowers which are closed at the time of maturity of
anthers and stigmas are termed cleistogamous.
simplest case the anthers are close to the stigmas, covering these
Self-pollination is effected in very various ways. In the
with pollen when they open; this occurs in a number of small
annual plants, also in Narcissus, Crocus, &c. In snowdrop and
other pendulous flowers the anthers form a cone around the style
and the pollen falls on to the underlying stigmas, or in erect
flowers the pollen may fall on to the stigmas which lie directly
beneath the opening anthers (e.g. Narthecium). In very many
cases the pollen is carried to the stigma by elongation, curvature
or some other movement of the filament, the style or stigma, or
corolla or some other part of the flower, or by correlated move-
ments of two or more parts. For instance, in many flowers
the filaments are at first directed outwards so that self-pollina-
tion is not possible, but later incline towards the stigmas and

POLLINATION, in botany, the transference of the pollen from the stamen to the receptive surface, or stigma, of the pistil of a flower. The great variety in the form, colour and scent of flowers (see FLOWER) is intimately associated with pollination which is effected by aid of wind, insects and other agencies. Pollen may be transferred to the stigma of the same flower-pollinate them (e.g. numerous Saxifragaceae, Cruciferae and self-pollination (or autogamy), or to the stigma of another flower on the same plant or another plant of the same species-crosspollination (or allogamy). Effective pollination may also occur between flowers of different species, or occasionally, as in the case of several orchids, of different genera-this is known as hybridization.

The method of pollination is to some extent governed by the distribution of the stamens and pistil. In the case of unisexual flowers, whether monoecious, that is, with staminate and pistillate flowers on one and the same plant, such as many of our native trees oak, beech, birch, alder, &c., or dioecious with staminate and pistillate flowers on different plants, as in willows and poplars, cross pollination only is possible. In bisexual or hermaphrodite flowers, that is, those in which both stamens and pistil are present, though self-pollination might seem the obvious course, this is often prevented or hindered by various arrangements which favour cross-pollination. Thus the anthers and stigmas in any given flower are often mature at different times; this condition, which is known as dichogamy and was first

others), or the style, which first projects beyond the anthers, shortens later on so that the anthers come into contact with the stigmas (e.g. species of Cactaceae), or the style bends so that the stigma is brought within the range of the pollen (e.g. species of Oenothera, Epilobium, most Malvaceae, &c.). In Mirabilis Jalapa and others the filaments and style finally become intertwined, so that pollen is brought in contact with the stigma. Selfpollination frequently becomes possible towards the end of the life of a flower which during its earlier stages has been capable only of cross-pollination. This is associated with the fact, so ably demonstrated by Darwin, that, at any rate in a large number of cases, cross-pollination yields better results, as measured by the number of seeds produced and the strength of the offspring, than self-pollination; the latter is, however, preferable to absence of pollination. In many cases pollen has no effect on the stigma of the same flower, the plants are selfsterile, in other cases external pollen is more effective (pré-potent) than pollen from the same flower; but in a very large number of cases experiment has shown that there is little or no difference

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between the effects of external pollen and that from the same flower.

Cross-pollination may occur between two flowers on the same plant (geitonogamy) or between flowers on distinct plants (xenogamy). The former, which is a somewhat less favourable method than the latter, is effected by air-currents, insect agency, the actual contact between stigmas and anthers in neighbouring flowers, where, as in the family Compositae, flowers are closely crowded, or by the fall of the pollen from a my ban ng algaja vay s od Hay to weley-dainsong baldw darw and botie in both aqw botrgnof-s

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polo so noitanillog Lainga som to algmax3 gnofodt legi) stein2 yd noma noda od of bagnid ei nossa nol & ba ng uldini nibns ms ol gnidong ni od ogral A 19ine-led a

(From Darwin's Different Forms of Flowers by permission.) bas

FIG. 2. Diagram of the flowers of the three forms of Lythrum salicaria in their natural position, with the petals and calyx to amgita removed on the near side.

The dotted lines with the arrow show the directions in which pollen must be carried to each stigma to ensure full fertility.

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higher on to the stigmas of a lower flower. Anton Kerner has
shown that crowded inflorescences such as those of Compositae
and Umbelliferae are especially adapted for geitonogamy.
Xenogamy is of course the only possible method in diclinous
plants; it is also the usual method in monoclinous plants, owing
to the fact that stamens and carpels often mature at different
times (dichogamy), the plants being proterandrous or protero-
gynous. Even in homogamous flowers cross-pollination is in al-animed
large proportion of cases the effective method, at any rate at
first, owing to the relative position of anther and stigma or the
fact that the plant is self-sterile.

The subject of heterostyly was investigated by Darwin (see bis Forms of Flowers) and later by Hildebrand. In the case of a dimorphic flower, such as Primula, four modes of pollination are possible, two distinguished by Darwin as legitimate, between anthers and stigmas on corresponding levels, and two so-called illegitimate unions, between anthers and stigmas at different trimorphic flower such as Lythrum

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B, male flowers; 1 before; 2, after spreading of the petals. A male flower has floated alongside a female and one of its anthers, which have opened to set free the pollen, is in contact with a stigma. a, anther.

C. Animal-pollinated plants, Zoidiophilae, are subdivided according
to the kind of animal by agency of which pollination is
effected, thus:
a. Bat-pollinated, Chiropterophilae.-A Freycinetia, native of
Java, and a species of Bauhinia in Trinidad are visited by
obats which transfer the pollen.

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aid is sought, and there are also numerous devices for protecting the pollen and nectar from rain and dew or from the visits of those insects which would not serve the purpose of pollen-transference (unbidden guests). The following subdivisions have been suggested

A. Pollen Flowers.-These offer only pollen to their visitors, as species of anemone, poppy, rose, tulip, &c. They are simple in structure and regular in form, and the generally abundant pollen is usually freely exposed.

B. Nectar Flowers.-These contain nectar and include the following groups:

1. Flowers with exposed nectar, readily visible and accessible to all visitors. These are very simple, open and generally regular flowers, white, greenish-yellow or yellow in colour and are chiefly visited by insects with a short proboscis, such as short-tongued wasps and flies, also beetles and more rarely bees. Examples are Umbelliferae as a family, saxifrages, holly, Acer, Rhamnus, Euonymus, Euphorbia, &c.

2. Flowers with nectar partly concealed and visible only in bright sunshine. The generally regular flowers are completely open only in bright sunshine, closing up into cups at other times. Such are most Cruciferae, buttercups, king-cup (Caltha), Potentilla. White and yellow colours predominate and insects with a proboscis of medium length are the common pollinating agents, such as short-tongued bees.

3. Flowers with nectar concealed by pouches, hairs, &c. Regular flowers predominate, e.g. Geranium, Cardamine pratensis, mallows, Rubus, Oxalis, Epilobium, &c., but many species show more or less well-marked median symmetry (zygomorphism) as Euphrasia, Orchis, thyme, &c., and red, blue and violet are the usual colours. Long-tongued insects such as the honey-bee are the most frequent visitors.

4. Social flowers, whose nectar is concealed as in (3), but the flowers are grouped in heads which render them strikingly conspicuous, and several flowers can be simultaneously pollinated. Such are Compositae as a class, also Scabiosa, Armeria (sea-pink) and others. 5. Hymenopterid flowers, which fall into the following groups: Bee-flowers proper, humble-bee flowers requiring a longer proboscis to reach the nectar, wasp-flowers such as fig-wort (Scrophularia nodosa) and ichneumon flowers such as tway-blade (Listera ovata).

The shapes and colours are extremely varied; bilaterally symmetrical forms are most frequent with red, blue or violet colours. Such are Papilionaceous flowers, Violaceae, many Labiatae, Scrophulariaceae and others. Many are highly specialized so that pollination can be effected by a few species only. Examples of more special mechanisms are illustrated by Salvia (fig. 9). The long connective of the single stamen is hinged to the short filament and has a shorter arm ending in a blunt process and a longer arm bearing a half-anther. A large bee in probing for honey comes in contact with the end of the short arm of the lever and causes the longer arm to descend and the pollen is deposited on the back of the insect (fig. 9, 1). In a later stage (fig. 9, 2) the style elongates and the forked stigma occupies the same position as the anther in fig. 9, I.

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(From a drawing in the Botanical Gallery at the British Museum.) FIG. 7.-Flower of Datura sanguinea visited by humming-bird Docimastes ensiferus.

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FIG. 8.-1, anther; 2, pollen grain of Hollyhock (Althaca rosea) enlarged. The pollen grain bears numerous spines, the lark spots indicate thin places in the outer wall.

d. Insect-pollinated, Entomophilae, a very large class characterized by sticky pollen grains, the surface of which bears spines, warts or other projections (fig. 8) which facilitate adhesion to some part of the insect's body, and a relatively small stigma with a sticky surface. The flowers have an attractive floral envelope, are scented and often contain honey or a large amount of pollen; by these means the insect is enticed to visit it. The form, colour and scent of the flower vary widely. according to the class of insect whose

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