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as an inert" brown body" in the body-cavity or is discharged to the exterior by the alimentary canal of the new polypide. This is formed as a two-layered "polypide-bud," which usually develops from the inner side of the zooecial wall, and soon occupies the place of the previous polypide. The inner layer of the polypide-bud gives rise to the structures usually regarded as ectodermic and endodermic, the outer layer to the mesodermic organs.

described from Palaeozoic strata. They constitute a small proportionmented substances assume a spheroidal form, which either remains of the recent Polyzoa. The Cheilostomata are usually believed to have made their appearance in the Jurassic period. They are the dominant group at the present day, and are represented by a large number of genera and species. The Phylactolaemata are a small group confined to fresh water, and possess clear indications of adaptation to that habitat. The fresh-water fauna also contains a representative of the Entoprocta (Urnatella), two or three Ctenostomes, such as Victorella and Paludicella, and one or two species of Cheilostomata. With these exceptions, the existing Polyzoa are marine forms, occurring from between tide-marks to abyssal depths in the ocean.

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(After Allman.) FIG. 5. Zooid Plumatella, with expanded tentacles. a, Anus;

on

a

The Polyzoa are colonial animals, the colony (zoarium) originating in most cases from a free-swimming larva, which attaches itself to some solid object and becomes metamorphosed into the primary individual, or "ancestrula." In the Phylactolaemata, however, a new colony may originate not only from a larva, but also from a peculiar form of bud known as a statoblast, or by the fission of a fully-developed colony. The ancestrula inaugurates a process of budding, conof tinued by its progeny, and thus gives rise to the mature colony. In Loxosoma the buds break off as soon as they become mature, and a colonial form is thus hardly br, Tentacles, arranged assumed. In other Entoprocta the buds horseshoe retain a high degree of individuality, a shaped lopho- thread-like stolon giving off the cylindrical phore; stalks, each of which dilates at its end i, Ectocyst; into the body of a zooid. In some of the v, Caecum of stomach. Ctenostomata the colony is similarly constituted, a branched stolon giving off the zooids, which are not connected with one another. In the majority of Ectoprocta there is no stolon, the zooids growing out of one another and being usually apposed so as to form continuous sheets or branches. In the encrusting type, which is found in a large proportion of the genera, the zooids are usually in a single layer, with their orifices facing away from the substratum; but in certain species the colony becomes multilaminar by the continued superposition of new zooids over the free surfaces of the older ones, whose orifices they naturally occlude. zoarium may rise up into erect growths composed of a single layer of zooids, the orifices of which are all on one surface, or of two layers of zooids placed back to back, with the orifices on both sides of the fronds or plates. The rigid Cheilostomes which have this habit were formerly placed in the genus Eschara, but the bilaminar type is common to a number of genera, and there can be no doubt that it is not in itself an indication of affinity. The body-wall is extensively calcified in the Cyclostomata and in most Cheilostomata, which may form elegant network-like colonies, as in the unilaminar genus Retepora, or may consist of wavy anastomosing plates, as in the bilaminar Lepralia foliacea of the British coasts, specimens of which may have a diameter of many inches. In other Cheilostomes the amount of calcification may be much less, the supporting skeleton being largely composed of the organic material chitin. In Flustra and other forms belonging to this type, the zoarium is accordingly flexible, and either bilaminar or unilaminar. In many calcareous forms, both Cheilostomes and Cyclostomes, the zoarium is rendered flexible by the interposition of chitinous joints at intervals. This habit is characteristic of the genera Crisia, Cellaria, Catenicella and others, while it occurs in certain species of other genera. The form of the colony may thus be a good generic character, or, on the contrary, a single genus or even species may assume a variety of different forms. While nearly all Polyzoa are permanently fixed to one spot, the colonies of Cristatella and Lophopus among the Phylactolaemata can crawl slowly from place to place.

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Anatomy. The zooids of which the colonies of Ectoprocta are composed consist of two parts: the body-wall and the visceral mass (figs. 6, 9). These were at one time believed to represent two individuals of different kinds, together constituting a zooid. The visceral mass was accordingly termed the "polypide" and the body-wall which contains it the zooecium." This view depended principally on the fact that the life of the polypide and of the zooecium are not coextensive. It is one of the most remarkable facts in the natural history of the Polyzoa that a single zooecium may be tenanted by several polypides, which successively degenerate. The periodical histolysis may be partly due to the absence of specific excretory organs and to the accumulation of pigmented excretory substances in the wall of the alimentary canal. On the degeneration of the polypide, its nutritive material is apparently absorbed for the benefit of the zooid, while the pig

The polypide consists of a "lophophore" bearing a series of ciliated tentacles by which Diatoms and other microscopic bodies are collected as food, of a U-shaped alimentary canal, and of a central nervous system. While the mouth is invariably encircled by the bases of the tentacles, the anus lies within the series in the Entoprocta and outside it in the Ectoprocta. The lophophore is a simple circle in all Polyzoa except in the Phylactolaemata, where it typically has the form of a horse shoe outlined by the bases of the tentacles. In Fredericella belonging to this order it is, however, circular, but the systematic position of the genus is sufficiently indicated by its possession of an epistome," a lip-like structure guarding the anal side of the mouth in all Phylactolaemata and absent throughout the Gymnolaemata. The cavities of the hollow tentacles open into a circular canal which surrounds the oesophagus at the base of the lophophore. This is continuous with the general body-cavity in the Phylactolaemata, while in the Gymnolaemata it develops in the bud as a part of the body-cavity, from which it becomes completely separated. In the Entoprocta the tentacles are withdrawn by being infolded into the "vestibule," a depression of the oral surface which can be closed by a sphincter muscle. In the Ectoprocta they are retractile into an introvert, the "tentaclesheath (fig. 9), the external opening of which is the "orifice of the zooecium. In the Cyclostomata, further distinguished by the cylindrical or prismatic form of their highly calcified zooecia, the orifice is typically circular, without any definite closing organ. In the Cheilostomata it is closed by a chitinous (rarely calcareous) operculum" (fig. 9, C), while in the Ctenostomata it is guarded by a delicate membrane similar to a piece of paper rolled into a longitudinally creased cylinder. During retraction this collar lies concealed in the beginning of the introvert. It becomes visible when the polypide begins to protrude its tentacles, making its appearance through the orifice as a delicate hyaline frill through which the tentacles are pushed.

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In the Phylactolaemata the outermost layer of the bodywall is a flexible, uncalcified cuticle or "ectocyst," beneath which follow in succession the ectoderm, the muscular layers and the coelomic epithelium. In a few Gymnolaemata the ectocyst is merely chitinous, although in most cases the four vertical walls and the basal wall of the zooecium are calcareous. The free (frontal) wall may remain membranous and uncalcified, as in Membranipora (figs. 8 A, 9 A), but in many Cheilostomes the frontal surface is protected by a calcareous shield, which grows from near the free edges of the vertical walls and commonly increases in thickness as the zooecium grows older by the activity of the "epitheca," a layer of living tissue outside it. The bodywall is greatly simplified in the Gymnolaemata, in correlation with the functional importance of the skeletal part of the wall. Even the ectoderm can rarely be recognized as an obvious epithelium except in regions where budding is taking place, while muscular layers are always absent and a coelomic epithelium can seldom be observed. The body-cavity is, however, traversed by muscles, and by strands of mesodermic funicular tissue,' usually irregular, but sometimes constituting definite funiculi (fig. 6. x, x). This tissue is continuous from zooecium to zooecium

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(After Allman.)

a,

FIG. 6.-Zooid of Paludicella articulata (= ehrenbergi). Anus.

br, Expanded tentacles. Ectocyst.

i,

mr,

m, r', Parietovaginal muscles. Retractor muscle. Ovary. Oesophagus.

0,

oe,

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Caecum of stomach.
testis.

t,
x, x', Funiculi.

ect.

mes

species of Membranipora the "frontal membrane," or membranous free-wall, is protected by a series of calcareous spines, which start from its periphery and arch inwards. In Cribrilina similar spines

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through perforated "rosette-plates" in the dividing walls. In the Phylactolaemata a single definite funiculus passes from the bodywall to the apex of the stomach. This latter organ is pigmented in all Polyzoa, and is produced, in the Ectoprocta, beyond the point where the intestine leaves it into a conspicuous caecum (fig. 6, v). The nervous system is represented by a ganglion situated between the mouth and the anus. The ovary (0) and the testis (1) of Ectoprocta are developed on the body-wall, on the stomach, or on the funiculus. Both kinds of reproductive organs may occur in a single zooecium, and the reproductive elements pass when ripe into the body-cavity. Their mode of escape is unknown in most cases. In some Gymnolaemata, polypides which develop an ovary possess a flask-shaped "intertentacular organ," situated between two of the tentacles, and affording a direct passage into the introvert for the eggs or even the spermatozoa developed in the same zooecium. In other cases the reproductive cells perhaps pass out by the atrophy of the polypide, whereby the body-cavity may become continuous with the exterior. The statoblasts of the Phylactolaemata originate on the funiculus, and are said to be derived partly from an ectodermic core possessed by this organ and partly from its external mesoderm (Braem), the former giving rise to the chitinous envelope and to a nucleated layer (fig. 7, ect), which later invaginates to form the inner vesicle of the polypide-bud. The mesodermic portion becomes charged with a yolk-like material (y), and, on the germination of the statoblast, gives rise to the outer layer (mes) of the bud. The production of a polypide by the statoblast thus differs in no essential respect from the formation of a polypide in an ordinary FIG. 9.-Diagrammatic Longitudinal Sections of Cheilostomatous zooecium. The statoblasts require a period of rest before germination, and Braem has shown that their property of floating at the surface may be beneficial to them by exposing them to the action of frost, which in some cases improves the germinating power. The occurrence of Phylactolaemata in the tropics an would show, however, without further evidence, that frost is not a factor essential for germination. The withdrawal of the extended polypide is effected by the contraction of the retractor muscles (fig. 6, mr), and must result in an increase in the volume of the contents of the bodycavity. The alternate increase and diminution of volume is easily understood in forms with flexsp, Anchoring spines of the statoblast. ible zooecia. Thus in the y, The yolk-like mesodermic mass. Phylactolaemata the contraction of the muscular body-wall exerts a pressure on the fluid of the body-cavity and is the cause of the protrusion of the polypide. In the Gymnolaemata protrusion is effected by the contraction of the parietal muscles, which pass freely across the body-cavity from one part of the body-wall to another. In the branching Ctenostomes the entire body-wall is flexible, so that the contraction of a parietal muscle acts equally on the two points with which it is connected. In encrusting Ctenostomes and in the Membranipora-like Cheilostomes (figs. 8 A, 9 A) the free surface or frontal wall is the only one in which any considerable amount of movement can take place. The parietal muscles (p.m.), which pass from the vertical walls to the frontal wall, thus act by depressing the latter and so exerting a pressure on the fluid of the bodyFIG. 8. Diagrammatic Transverse cavity. In Cheilostomata Sections. with a rigid frontal wall A, of Membranipora; B, of an Jullien showed that proimmature zooecium of Cribrilina; trusion and retraction were rendered possible by the p.m., Parietal muscles. existence of a "compensation-sac," in communication with the external water.

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(After Braem.)

FIG. 7.-Section of a Germinating Statoblast of Cristatella mucedo. ann, Chitinous annulus, containing aircavities which enable the statoblast to float.

ect, Thickened part of the ectoderm,
which will give rise to the inner
layer of the polypide- bud.
mes, Mesoderm, forming the outer layer

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of the bud.

In its most fully-developed condition (fig. 9, C) the compensationsac (c.s.) is a large cavity which lies beneath the calcified frontal wall and opens to the exterior at the proximal border of the operculum (fig. 10). It is joined to the rigid body-wall by numerous muscle-fibres, the contraction of which must exert a pressure on the fluid of the body-cavity, thereby protruding the polypide. The exchange of fluid in the sac may well have a respiratory significance, in addition to its object of facilitating the movements of the tentacles. The evolution of the arrangements for protruding the polypide seems to have proceeded along several distinct lines: (i.) In certain

are developed in the young zooecium, but they soon unite with one
another laterally, leaving rows of pores along the sutural lines
(fig. 10). The operculum retains its
continuity with the frontal membrane
(fig. 9, B) into which the parietal muscles
are still inserted. As indications that
the conditions described in Membranipora
and Cribrilina are of special significance
may be noted the fact that the ancestrula
of many genera which have well-developed
compensation-sacs in the rest of their
zooecia is a Membranipora-like individual
with a series of marginal calcareous spines,
and the further fact that a considerable
proportion of the Cretaceous Cheilos-
tomes belong either to the Membrani-
poridae or to the Cribrilinidae. (ii.) In
Scrupocellaria, Menipea and Caberea a
single, greatly dilated marginal spine, the
FIG. 10.-Zooecium
"scutum" or "fornix," may protect the
frontal membrane. (iii.) In Umbonula of Cribrilina, showing
the frontal
the entrance to the
membrane and parietal
muscles of the young zooecium are like compensation - sac
those of Membrani pora, but they become the proximal side of the
covered by the growth, from the proximal operculum (op).
and lateral sides, of a calcareous lamina covered externally
by a soft membrane. The arrangement is perhaps derivable
from a Cribrilina-like condition in which the outer layer of the
spines has become membranous while the spines themselves are
laterally united from the first. (iv.) In the Microporidae and
Steganoporellidae the body-cavity becomes partially subdivided
by a calcareous lamina ("cryptocyst," Jullien) which grows from
the proximal and lateral sides in a plane parallel to the frontal
membrane and not far below it. The parietal muscles are usually
reduced to a single pair, which may pass through foramina
("opesiules") in the cryptocyst to reach their insertion.There is
no compensation-sac in these families. (v.) Many of the Lepralioid
forms offer special difficulties, but the calcareous layer of the frontal
surface is probably a cryptocyst (as in fig. 9, C), the compensation-
sac being developed round its distal border. The "epitheca
noticed above is in this case the persistent frontal membrane.
(vi.) In Microporella the opening of the compensation-sacchas
become separated from the operculum by calcareous matter, and
is known as the "median pore." Jullien believed that this pore
opens into the tentacle-sheath, but it appears probable that it really
communicates with the compensation-sac and not with the tentacle-
sheath. The mechanism of protrusion in the Cyclostomata is a
subject which requires further examination.
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The most singular of the external appendages found in the Polyzoa are the avicularia and vibracula of the Cheilostomata. The avicularium is so called from its resemblance, in its most highly differentiated condition, to the head of a bird. In Bugula, for instance, a calcareous avicularium of this type is attached by a narrow neck to each zooecium. The avicularium can move as a whole by means of special muscles, and its chitinous lower jaw

or "mandible" can be opened and closed. It is regarded as a modified zooecium, the polypide of which has become vestigial, although it is commonly represented by a sense-organ, bearing tactile hairs, situated on what may be termed the palate. The operculum of the normal zooecium has become the mandible, while the occlusor muscles have become enormous. In the vibraculum the part representing the zooecium is relatively smaller, and the mandible has become the seta," an elongated chitinous lash which projects far beyond the zooecial portion of the structure. In Caberea, the vibracula are known to move synchronously, but co-ordination of this kind is otherwise unknown in the Polyzoa. The avicularia and vibracula give valuable aid to the systematic study of the Cheilostomata. In its least differentiated form the avicularium occupies the place of an ordinary zooecium (" vicarious avicularium "), from which it is distinguished by the greater development of the operculum and its muscles, while the polypide is normally not functional. Avicularia of this type occur in the common Flustra foliacea, in various species of Membranipora, and in particular in the Onychocellidae, a remarkable family common in the Cretaceous period and still existing. In the majority of Cheilostomes, the avicularia are, so to speak, forced out of the ordinary series of zooecia, with which they are rigidly connected. There are comparatively few cases in which, as in Bugula, they are mounted on a movable joint. Although at first sight the arrangement of the avicularia in Cheilostomes appears to follow no general law some method is probably to be made out on closer study. They occur in particular in relation with the orifice of the zooecium, and with that of the compensation-sac. This delicate structure is frequently guarded by an avicularium at its entrance, while avicularia are also commonly found on either side of the operculum or in other positions close to that structure. It can hardly be doubted that the function of these avicularia is the protection of the tentacles and compensation-sac. The suggestion that they are concerned in feeding does not rest on any definite evidence, and is probably erroneous. But avicularia or vibracula may also occur in other places on the backs of unilaminar erect forms, along the sutural lines of the zooecia and on their frontal surface. These are probably important in checking overgrowth by encrusting organisms, and in particular by preventing larvae from fixing on the zoarium. Vibracula are of less frequent occurrence than avicularia, with which they may coexist as in Scrupocellaria, where they occur on the backs of the unilaminar branches. In the so-called Selenariidae, probably an unnatural association of genera which have assumed a free discoidal form of zoarium, they may reach a very high degree of development, but Busk's suggestion that in this group they "may be subservient to locomotion " needs verification. Development and Affinities. It is generally admitted that the larva of the Entoprocta (fig. 11) has the structure of a Trochosphere. This appears to indicate that the Polyzoa are remotely allied to other phyla in which this type of larva prevails, and in particular to the Mollusca and Chaetopoda, as well as to the Rotifera, which are regarded as persistent Trochospheres. The praeoral portion (lower in fig. 11) constitutes the greater part of nph the larva and contains most of the viscera. It is terminated by a well-developed structure (fg) corresponding with the apical sense-organ of ordinary TrochoT spheres, and an excretory organ (nph) of the type familiar in these larvae occurs on the ventral side of the stomach. The central nervous system (x) is highly developed, and in Loxosoma bears a pair of eyes. The larva swims by a ring of cilia, which corresponds with the praeoral circlet of a Trochosphere. The oral surface, on which are situated the mouth (m) and anus (a), is relatively small. The apical senseorgan is used for temporary attachment to the maternal vestibule in which development takes place, but permanent fixation is effected by the oral surface. This is followed by the atrophy of many of the larval organs, including the brain, the sense-organ and the ciliated ring. The alimentary canal persists and revolves in the median plane through an angle of 180°, accompanied by part of the larval vestibule, the space formed by the retraction of the oral surface. The vestibule breaks through to the exterior, and the tentacles, which have been developed within it, are brought into relation with the external water.

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VISOS

(After Hatschek.)

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FIG. 11.-Larva of Pedicellina.

a,

Anus.

fg,

Apical sense-organ.

hg,

Intestine.

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m,

Ventral wall of stomach.
Mouth.

nph, Excretory organ.

x,

Brain.

In the common and widely-distributed Cheilostome, Membrani

pora pilosa, the pelagic larva is known as Cyphonautes, and it has a structure not unlike that of the larval Pedicellina. The principal differences are the complication of the ciliated band, the absence of the excretory organ, the great lateral compression of the body, the possession of a pair of shells protecting the sides, the presence of an organ known as the " pyriform organ," and the occurrence of a sucker in a position corresponding with the depression seen between (m) and (a) in fig. II. Fixation takes place by means of this sucker, which is everted for the purpose, part of its epithelium becoming the basal ectoderm of the ancestrula. The pyriform organ has probably assisted the larva to find an appropriate place for fixation (cf. Kupelwieser, 18); but, like the alimentary canal and most of the other larval organs, it undergoes a process of histolysis, and the larva becomes the ancestrula, containing the primary brown body derived from the purely larval organs. The polypide is formed, as in an ordinary zooecium after the loss of its polypide, from a polypide-bud.

The Cyphonautes type has been shown by Prouho (24) to occur in two or three widely different species of Cheilostomata and Ctenostomata in which the eggs are laid and develop in the external water. In most Ectoprocta, however, the development takes place internally or in an ovicell, and a considerable quantity of yolk is present. The alimentary canal, which may be represented by a vestigial structure, is accordingly not functional, and the larva does not become pelagic. A pyriform organ is present in most Gymnolaemata as well as the sucker by which fixation is effected. As in the case of Cyphonautes, the larval organs degenerate and the larva becomes the ancestrula from which a polypide is developed as a bud. In the Cyclostomata the primary embryo undergoes repeated fission without developing definite organs, and each of the numerous pieces so formed becomes a free larva, which possesses no alimentary canal. Finally, in the Phylactolaemata, the larva becomes an ancestrula before it is hatched, and one or several polypides may be present when fixation is effected.

The development of the Ectoprocta is intelligible on the hypothesis that the Entoprocta form the starting-point of the series. On the view that the Phylactolaemata are nearly related to Phoronis (see PHORONIDEA), it is extremely difficult to draw any conclusions with regard to the significance of the facts of development. If the Phylactolaemata were evolved from the type of structure represented by Phoronis or the Pterobranchia (q.v.), the Gymnolaemata should be a further modification of this type, and the comparative study of the embryology of the two orders would appear to be meaningless. It seems more natural to draw the conclusion that the resemblances of the Phylactolaemata to Phoronis are devoid of phylogenetic significance.

BIBLIOGRAPHY.-For general accounts of the structure and development of the Polyzoa the reader's attention is specially directed to 12, 14, 6, 25, 1, 2, 17, 26, 18, 23, 3, in the list given below; for an historical account to I; for a full bibliography of the group, to 22; for fresh-water forms, to 1-3, 7-10, 17; for an indispensable synonymic list of recent marine forms, to 15; for Entoprocta, to 10, 11, 24; for the classification of Gymnolaemata, to 21, 14, 4, 13, 20; for Palaeontology, to 27, 22.

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References to important works on the species of marine Polyzoa by Busk, Hincks, Jullien, Levinsen, MacGillivray, Nordgaard, Norman, Waters and others are given in the Memoir (22) by Nickles and Bassler. (1) Allman, Monogr. Fresh-water Polyzoa," Ray Soc. (1856). (2) Braem, "Bry. d. süssen Wassers," Bibl. Zool. Bd. ii. Heft 6 (1890). (3) Braem, Entwickel. v. Plumatella," ibid., Bd. x. Heft 23 (1897). (4) Busk, " Report on the Polyzoa," Challenger" Rep. pt. xxx. (1884), 50 (1886). (5) Caldwell," Phoronis," Proc. Roy. Soc. (1883), xxxiv. 371. (6) Calvet, "Bry, Ectoproctes Marins,' Trav. Inst. Montpellier (new series), Mém. 8 (1900). (7) Cori, "Nephridien d. Cristatella," Zeitschr. wiss. Zool. (1893), lv. 626. (8) Davenport, "Cristatella," Bull. Mus. Harvard (1890-1891), xx. 101. (9) Davenport, "Paludicella," ibid. (1891-1892), xxii. I. (10) Davenport, "Urnatella," ibid. (1893), xxiv. 1. (11) Ehlers, Pedicellineen," Abh. Ges. Göttingen (1890), xxxvi. (12) Harmer, Polyzoa," Cambr. Nat. Hist. (1896), ii. 463; art. Polyzoa, Ency. Brit. (10th ed., 1902), xxxi. 826. (13) Harmer, Morph. Cheilostomata," Quart. Journ. Mic. Sci. (1903), xlvi. 263. (14) Hincks, Hist. Brit. Mar. Pol." (1880). (15) Jelly, Syn. Cat. Recent Mar. Bry." (1889). (16) Jullien and Calvet, Bryozoaires," Rés camp. sci. prince de Monaco (1903), xxiii. (17) Kraepelin, "Deutsch. Süsswasser-Bry.," Abh, Ver. Hamburg (1887), x.; (1892), xii. (18) Kupelwieser, "Cyphonautes," Zoologica (1906), Bd. xix. Heft 47. (19) Lankester, art. Polyzoa," Ency. Brit. (9th ed., 1885), xix. 429. (20) Levinsen, "Bryozoa," Vid. Medd. Naturh. Foren. (Copenhagen, 1902). (21) MacGillivray, "Cat. Mar. Pol. Victoria," P. Roy. Soc. Victoria (1887), xxiii. 187. (22) Nickles and Bassler, Synopsis Amer. Foss. Bry.," Bull.. US. Geol. Survey (1900), No. 173. (23) Pace, "Dev. Flustrella,' Quart. Journ. Mic. Soc. (1906), 50, pt. 3, 435. (24) Prouho, "Loxosomes," Arch. Zool. Exp. (2) (1891), ix. 91. (25) Prouho, Bryozoaires," ibid. (2) (1892), x. 557. (26) Seeliger, Larven u. Verwandtschaft," Zeitschr. wiss. Zool. (1906), Ixxxiv. I.. (27) Ulrich, Fossil Polyzoa," in Zittel's Text-book of Palaeontology. Eng. ed. (1900), i. 257.

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dibns Πίστα

POMADE, or POMATUM, a scented ointment, used formerly | axils of some of which proceed the brilliant scarlet flowers. for softening and beautifying the skin, as a lip-salve, &c., but These are raised on a short stalk, and consist of a thick fleshy now principally applied to the hair. It was made originally cylindrical or bell-shaped calyx-tube, with five to seven short from the juice of apples (Lat. pomum), whence the name. lobes at the top. From the throat of the calyx proceed five to POMANDER (from Fr. pomme d'ambre, i.e. apple of amber), a ball made of perfumes, such as ambergris (whence the name), musk, civet, &c., and formerly worn or carried in a case, also known by the same name, as a protection against infection in times of pestilence or merely as a useful article to modify bad smells. The globular cases which contained the "pomanders were hung from a neck-chain or attached to the girdle, and were usually perforated and made of gold or silver. Sometimes they contained several partitions, in each of which was placed a different perfume. There is an early Spanish pomander set with emeralds, and a fine 16th-century one, dredged from the Thames, in the British Museum.

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FIG. 1.-Pomegranate, Punica Granatum, flowering branch, half natural size.

POMBAL, SEBASTIÃO JOSE DE CARVALHO E MELLO, MARQUESS OF (1699-1782), Portuguese statesman, was born at Soure near Pomba, on the 13th of May 1699. He was the son of Manoel de Carvalho e Athayde, a country gentleman (fidalgo) and of his wife D. Theresa Luiza de Mendonça e Mello. He studied law at Coimbra University, served for a short time as a private in the army, and afterwards lived the life of a man about town in Lisbon, sharing in the diversions of the "Mohocks" who then infested the streets. In 1733 he abducted and married D. Theresa de Noronha, a widow belonging to one of the most distinguished families in Portugal. He then retired to Soure, where, on the recommendation of Cardinal de Motta, King John V. commissioned him to write a series of biographical studies. In 1739 he was sent as Portuguese ambassador to London, where he remained until 1745. He was then transferred to Vienna. His first wife having died on the 7th of January 1739, he married, on the 18th of December 1745, Leonora Ernestine Daun, daughter of General Count Daun. In 1749 he was recalled to take up the post of secretary of state for foreign affairs and war. The appointment was ratified on the 3rd of August 1750, by King Joseph, who had succeeded John V. in that year. Carvalho's career from 1750 to 1777 is part of the history of Portugal. Though he came into power only in his 51st year, without previous administrative experience, he was able to reorganize Portuguese education, finance, the army and the navy. He also built up new industries, promoted the development of Brazil and Macao, and expelled the Jesuits. His complete ascendancy over the mind of King Joseph dates from the time of the great Lisbon earthquake (Nov. 1, 1755). Though the famous words "Bury the dead and feed the living" were probably not spoken by him, they summarize his action at this time of calamity. In June 1759 his suppression of the so-called "Tavora plot gained for him the title of count of Oeyras; and in September 1770 he was made marquess of Pombal. His severe administration had made many enemies, and his life had been attempted in 1769. Soon after the death of King Joseph, in 1777, Pombal was dismissed from office; and he was only saved from impeachment by the death of his bitterest opponent, the queen-mother, (After Eichler, from Strasburger's Lehrbuch der Botanik, by permission of Gustav Mariana Victoria, in January 1781. On the 16th of August a royal decree forbade him to reside within twenty leagues of the court. He died at Pombal on the 8th of May 1782.

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See, in addition to the works dealing with the period 1750-1777 and quoted under PORTUGAL: History; S.J.C.M. (Pombal), Relação abreviada, &c. (Paris, 1758); Memoirs of the Court of Portugal, &c. (London, 1765); Anecdotes du ministère de Pombal (Warsaw, 1781); Administration du marquis de Pombal (4 vols., Amsterdam, 1787); Cartas.. do marques de Pombal (3 vols., Lisbon, 1820-1824); J. Smith, Count of Carnota, Memoirs of the Marquess of Pombal, &c. (London, 1843); F. L. Gomes, Le Marquis de Pombal, &c. (Paris, 1869); B. Duhr (S.J.), Pombal, &c. (Freiburg im Breisgau, 1891); C. J. de Menezes, Os Jesuitas e o marques de Pombal (Oporto, 1893). See also articles in the Revue des deux mondes for September 1870; the Revue bleue for September 1889, and the Revue historique for September 1895 and January 1896.

POMEGRANATE. The pomegranate (Punica Granatum) is of exceptional interest by reason of its structure, its history, and its utility. It forms a tree of small stature, or a bush, with opposite or alternate, shining, lance-shaped leaves, from the

1, Flower cut lengthwise; the 3. Same cut across, showing
petals have been removed.
seeds.
2, Fruit, about one-third natural
4, Seed, natural size.

size.

seven roundish, crumpled, scarlet or crimson petals, and below them very numerous slender stamens. The pistil consists of two rows of carpels placed one above another, both rows embedded in, and partially inseparate from, the inner surface of the calyxtube. The styles are confluent into one slender column. The fruit, which usually attains the size of a large orange, consists

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A, Floral diagram. B, Longitudinal section of the ovary. of a hard leathery rind, enclosing a quantity of pulp derived from the coats of the numerous seeds. This pulp, filled as it is with refreshing acid juice, constitutes the chief value of the tree. The more highly cultivated forms contain more of it than the wild or half-wild varieties. The great structural peculiarity consists in the presence of the two rows of carpels one above another (a state of things which occurs exceptionally in apples and oranges), and in the fact that, while in the lower series the seeds are attached to the inner border or lower angle of the cavity, they occupy the outer side in the upper series, as if during growth the upper whorl had become completely bent over.

By Bentham and Hooker the Punica is included as an anomalous genus in the order Lythraceae; others consider it more nearly allied to the myrtles; while its peculiarities are so great as, in the opinion of many botanists, to justify its inclusion in a

separate order, Punicaceae. Not only is the fruit valuable in hot countries for the sake of its pulp, but the rind and the bark and the outer part of the root (containing the alkaloid pelletierine) are valuable as astringents. The bark of the root is likewise valued as an anthelmintic in cases of tape-worm.

The tree is wild in Afghanistan, north-western India, and the districts south and south-west of the Caspian, but it has been so long cultivated that it is difficult to say whether it is really native in Palestine and the Mediterranean region. It has been cited as wild in northern Africa, but this appears to be a mistake. Professor Bayley Balfour met with a wild species, heretofore unknown, in the island of Socotra, the flowers of which have only a single row of carpels, which suggests the inference that it may have been the source of the cultivated varieties. But, on the other hand, in Afghanistan, where Aitchison met with the tree truly wild, a double row of carpels was present as usual. The antiquity of the tree as a cultivated plant is evidenced by the Sanskrit name Dāḍimba, and by the references to the fruit in the Old Testament, and in the Odyssey, where it is spoken of as cultivated in the gardens of the kings of Phaeacia and Phrygia. The fruit is frequently represented on ancient Assyrian and Egyptian sculptures, and had a religious significance in connexion with several Oriental cults, especially the Phrygian cult of Cybele (Arnob. v. 5 seq.; see also Baudissin, Studien, ii. 207 seq.). It was well known to the Greeks and Romans, who were acquainted with its medicinal properties and its use as a tanning material. The name given by the Romans, malum punicum, indicates that they received it from Carthage, as indeed is expressly stated by Pliny; and this circumstance has given rise to the notion that the tree was indigenous in northern Africa. On a review of the whole evidence, botanical, literary and linguistic, Alphonse de Candolle (Origin of Cultivated Plants) pronounces against its African origin, and decides in favour of its source in Persia and the neighbouring countries. According to Saporta, the pomegranate existed in a fossil state in beds of the Pliocene epoch near Meximieux in Burgundy. The pomegranate is sometimes met with in cultivation against a wall in England, but it is too tender to withstand a severe winter. The double-flowered varieties are specially desirable for the beauty and long duration of their flowers.

POMERANIA (German, Pommern), a territory of Germany and a maritime province of Prussia, bounded on the N. by the Baltic, on the W. by Mecklenburg, on the S. by Brandenburg, and on the E. by West Prussia. Its area is 11,630 sq. m., and the population in 1905 was 1,684,125, showing a density of 145 inhabitants to the square mile. The province is officially divided into the three districts of Stralsund, Stettin and Köslin, but more historical interest attaches to the names of Vorpommern and Hinterpommern, or Hither and Farther Pomerania, the former being applied to the territory to the west, and the latter to that to the east of the Oder. Pomerania is one of the flattest parts of Germany, although east of the Oder it is traversed by a range of low hills, and there are also a few isolated eminences to the west. Off the west coast, which is very irregular, lie the islands of Rügen, Usedom and Wollin; the coast of Farther Pomerania is smooth in outline and is bordered with dunes, or sandbanks. Besides the Oder and its affluents, the chief of which are the Peene, the Ucker and the Ihna, there are several smaller rivers flowing into the Baltic; a few of these are navigable for ships, but the greater number only carry rafts. Many of them end in small lakes, which are separated from the sea by narrow strips of land, through which the water escapes by one or more outlets. The interior of the province is also thickly sprinkled with lakes, the combined area of which is equal to about one-twentieth of the entire surface.

The soil of Pomerania is for the most part thin and sandy, but patches of good land are found here and there. About 55% of the whole is under tillage, while 16% consists of meadow and pasture and 21% is covered by forests. The principal crops are potatoes, rye and oats, but wheat and barley are grown in the more fertile districts; tobacco, flax, hops and beetroot are also cultivated. Agriculture is still carried on in a somewhat

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primitive fashion, and as a rule the livestock is of an inferior quality, though the breed of horses, of a heavy build and mostly used in agriculture, is held in high esteem. Large flocks of sheep are kept, both for their flesh and their wool, and there are in the province large numbers of horned cattle and of pigs, Geese and goose feathers form lucrative articles of export. Owing to the long line of coast and the numerous lakes, fishing forms an important industry, and large quantities of herrings, eels and lampreys are sent from Pomerania to other parts of Germany. With the exception of the almost inexhaustible layers of peat, the mineral wealth of the province is insignificant. Its industrial activity is not great, but there are manufactures of machinery, chemicals, paper, tobacco and sugar; these are made chiefly in or near the large towns, while linen-weaving is practised as a domestic industry. Ship-building is carried on at Stettin and at several places along the coast. The commerce of Pomerania is in a flourishing condition, its principal ports being Stettin, Stralsund and Swinemünde. Education is provided for by a university at Greifswald and by numerous schools. The province sends 14 members to the German Reichstag, and 26 to the Prussian house of representatives. The heir to the Prussian crown bears the title of governor of Pomerania.

History. In prehistoric times the southern coast of the Baltic seems to have been occupied by Celts, who afterwards made way | for tribes of Teutonic stock. These in their turn migrated to other settlements and were replaced, about the end of the 5th century of our era, by Slavonic tribes, the Wilzi and the Pomerani. The name of Pomore, or Pommern, meaning "on the sea," was given to the district by the latter of the tribes about the time of Charlemagne, and it has often changed its political and geographical significance. Originally it seems to have denoted the coast district between the Oder and the Vistula, a territory which was at first more or less dependent on Poland, but which, towards the end of the 12th century, was ruled by two native princes, who took the title of duke about 1170 and admitted the authority of the German king in 1181. Afterwards Pomerania extended much farther to the west, while being correspondingly curtailed on the east, and a distinction was made between Slavinia, or modern Pomerania, and Pomerellen. The latter, corresponding substantially to the present province of West Prussia, remained subject to Poland until 1309, when it was divided between Brandenburg and the Teutonic Order. Christianity was introduced in the 12th century, a bishopric being founded in the Island of Wollin, and its advance went rapidly hand in hand with the Germanizing of the district.

The history of Pomerania, as distinct from that of Pomerellen, consists mainly of an almost endless succession of divisions of territory among the different lines of the ducal house, and of numerous expansions and contractions of territory through constant hostilities with the elector of Brandenburg, who claimed to be the immediate feudal superior of Pomerania, and with other neighbouring rulers. The names of Vorpommern and Hinterpommern were at first synonymous with Pomerania. proper, or Slavinia and Pomerellen, but towards the close of the 14th century they were transferred to the two duchies into which the former was divided. In 1625 the whole of Pomerania became united under the sway of Duke Bogislaus XIV., and on his death without issue, in 1637, Brandenburg claimed the duchy by virtue of a compact made in 1571. In the meantime, however, Pomerania had been devastated by the Thirty Years' War and occupied by the Swedes, who had taken possession of its towns and fortresses. At the peace of Westphalia they claimed the duchy, in opposition to the elector of Brandenburg, and the result was that the latter was obliged to content himself with eastern Pomerania (Hinterpommern), and to see the western part (Vorpommern) awarded to Sweden. In 1720, by the peace of Stockholm, Swedish Pomerania was curtailed by extensive concessions to Prussia, but the district to the west of the Peene remained in the possession of Sweden until the general European settlement of 1815. Then Sweden assigned her German possessions to Denmark in exchange for Norway, whereupon Prussia, partly by purchase and partly by the cession

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