[1] The most ancient code known, that of Khammurabi, is dealt with in
the article BABYLONIAN LAW.
CODE NAPOLEON, the first code of the French civil law, known at first as
the _Code civil des Francais_, was promulgated in its entirety by a law
of the 30th Ventose in the year XII. (31st of March 1804). On the 3rd of
September 1807 it received the official name of Code Napoleon, although
the part that Napoleon took in framing it was not very important. A law
of 1818 restored to it its former name, but a decree of the 27th of
March 1852 re-established the title of Code Napoleon. Since the 4th of
September 1870 the laws have quoted it only under the name of the Code
Civil.
Never has a work of legislation been more national in the exact sense of
the word. Desired for centuries by the France of the _ancien regime_,
and demanded by the _cahiers_ of 1789, this "code of civil laws common
to the whole realm" was promised by the constitution of 1791. However,
the two first assemblies of the Revolution were able to prepare only a
few fragments of it. The preparation of a coherent plan began with the
Convention. The _ancien regime_ had collected and adjusted some of the
material. There was, on the one hand, a vast juridical literature which
by eliminating differences of detail, had disengaged from the various
French "customs" the essential part which they had in common, under the
name of "common customary law"; on the other hand, the Roman law current
in France had in like manner undergone a process of simplification in
numerous works, the chief of which was that of Domat; while certain
parts had already been codified in the _Grandes Ordonnances_, which were
the work of d'Aguesseau. This legacy from the past, which it was desired
to preserve within reason, had to be combined and blended with the laws
of the Revolution, which had wrought radical reforms in the conditions
affecting the individual, the tenure of real property, the order of
inheritance and the system of mortgages. Cambaceres, as the
representative of a commission of the Convention, brought forward two
successive schemes for the Code Civil. As a member of one of the
councils, he drew up a third under the Directory, and these projected
forms came in turn nearer and nearer to what was to be the ultimate form
of the code. So great was the interest centred in this work, that the
law of the 19th Brumaire, year VIII., which, in ratification of the
previous day's _coup d'etat_ nominated provisional consuls and two
legislative commissions, gave injunctions to the latter to draw up a
scheme for the Code Civil. This was done in part by one of the members,
Jacqueminot, and finally under the constitution of the year VIII., the
completion of the work was taken in hand. The legislative machinery
established by this constitution, defective as it was in other respects,
was eminently suited for this task. Indeed, all projected laws emanated
from the government and were prepared by the newly established council
of state, which was so well recruited that it easily furnished qualified
men, mostly veterans of the revolution, to prepare the final scheme. The
council of state naturally possessed in its legislative section and its
general assembly bodies both competent and sufficiently limited to
discuss the texts efficiently. The _corps legislatif_ had not the right
of amendment, so could not disturb the harmony of the scheme. It was in
the discussions of the general assembly of the council of state that
Napoleon took part, in 97 cases out of 102 in the capacity of chairman,
but, interesting as his observations occasionally are, he cannot be
considered as a serious collaborator in this great work.
Those responsible for the scheme have in the main been very successful
in their work; they have generally succeeded in fusing the two elements
which they had to deal with, namely ancient French law, and that of the
Revolution. The point in which their work is comparatively weak is the
system of hypothec (q.v.), because they did not succeed in steering a
middle course between two opposite systems, and the law of the 23rd of
March 1855 (_sur la transcription en matiere hypothecaire_) was
necessary to make good the deficiency. A fault frequently found with the
Code Civil is that its general divisions show a lack of logic and
method, but the division is practically that of the Institutes of
Justinian, and is about as good as any other: persons, things,
inheritance, contracts and obligations, and finally, in place of
actions, which have no importance for French law except from the point
of view of procedure, privileges and hypothecs, as in the ancient
_coutumes_ of France, and prescription. It is, _mutatis mutandis_,
practically the same division as that of Blackstone's Commentaries.
Of late years other objections have been expressed; serious omissions
have been pointed out in the Code; it has not given to personal property
the importance which it has acquired in the course of the 19th century;
it makes no provision for dealing with the legal relations between
employers and employed which modern complex undertakings involve; it
does not treat of life insurance, &c. But this only proves that it could
not foretell the future, for most of these questions are concerned with
economic phenomena and social relations which did not exist at the time
when it was framed. The Code needed revising and completing, and this
was carried out by degrees by means of numerous important laws. In 1904,
after the celebration of the centenary of the Code Civil, an
extra-parliamentary commission was nominated to prepare a revision of
it, and at once began the work.
The influence of the Code Civil has been very great, not only in France
but also abroad. Belgium has preserved it, and the Rhine provinces only
ceased to be subject to it on the promulgation of the civil code of the
German empire. Its ascendancy has been due chiefly to the clearness of
its provisions, and to the spirit of equity and equality which inspires
them. Numerous more recent codes have also taken it as a model: the
Dutch code, the Italian, and the code of Portugal; and, more remotely,
the Spanish code, and those of the Central and South American republics.
In the present day it is rivalled by the German civil code, which,
having been drawn up at the end of the 19th century, naturally does not
show the same lacunae or omissions. It is inspired, however, by a very
different spirit, and the French code does not suffer altogether by
comparison with it either in substance or in form.
See _Le Code Civil, livre du centenaire_ (Paris, 1904), a collection
of essays by French and foreign lawyers. (J. P. E.)
CODIAEUM, a small genus of plants belonging to the natural order
Euphorbiaceae. One species, _C. variegatum_, a native of Polynesia, is
cultivated in greenhouses, under the name of croton, for the sake of its
leaves, which are generally variegated with yellow, and are often
twisted or have the blades separated into distinct portions.
CODICIL (Lat. _codicillus_, a little book or tablet, diminutive of
_codex_), a supplement to a will (q.v.), containing anything which a
testator desires to add, or which he wishes to retract, to explain or to
alter. In English law a codicil requires to be executed with the same
formalities as a will under the Wills Act 1837.
CODILLA, the name given to the broken fibres which are separated from
the flax during the scutching process. On this account it is sometimes
termed scutching tow. Quantities of this material are used along with
heckled tow in the production of tow yarns.
CODINUS, GEORGE [GEORGIOS KODINOS], the reputed author of three extant
works in Byzantine literature. Their attribution to him is merely a
matter of convenience, two of them being anonymous in the MSS. Of
Codinus himself nothing is known; it is supposed that he lived towards
the end of the 15th century. The works referred to are the following:--
1. _Patria_ ([Greek: Ta Patria tes Konstantinoupoleos]), treating of the
history, topography, and monuments of Constantinople. It is divided
into five sections: (_a_) the foundation of the city; (_b_) its
situation, limits and topography; (_c_) its statues, works of art, and
other notable sights; (_d_) its buildings; (_e_) the construction of the
church of St Sophia. It was written in the reign of Basil II.
(976-1025), revised and rearranged under Alexius I. Comnenus
(1081-1118), and perhaps copied by Codinus, whose name it bears in some
(later) MSS. The chief sources are: the _Patria_ of Hesychius Illustrius
of Miletus, an anonymous (_c._ 750) brief chronological record ([Greek:
Parastaseis syntomoi chronikai]), and an anonymous account ([Greek:
diegesis]) of St Sophia (ed. T. Preger in _Scriptores originum
Constantinopolitanarum_, fasc. i., 1901, to be followed by the _Patria_
of Codinus). Procopius, _De Aedificiis_ and the poem of Paulus
Silentiarius on the dedication of St Sophia should be read in connexion
with this subject.
2. _De Officiis_ ([Greek: Peri ton Ophphikion]), a sketch, written in an
unattractive style, of court and higher ecclesiastical dignities and of
the ceremonies proper to different occasions. It should be compared with
the _De Cerimoniis_ of Constantine Porphyrogenitus.
3. A chronological outline of events from the beginning of the world to
the taking of Constantinople by the Turks (called Agarenes in the MS.
title). It is of little value.
Complete editions are (by I. Bekker) in the Bonn _Corpus scriptorum
Hist. Byz._ (1839-1843, where, however, some sections of the _Patria_
are omitted), and in J. P. Migne, _Patrologia graeca_, clvii.; see
also C. Krumbacher, _Geschichte der byzantinischen Litteratur_ (1897).
COD-LIVER OIL (_Oleum Morrhuae_, or _Oleum Jecoris Aselli_), the oil
obtained from the liver of the common cod (_Gadus morrhua_). In the
early process for extracting the oil the livers were allowed to putrefy
in wooden tubs, when oils of two qualities, one called "pale oil," and
the other "light brown oil," successively rose to the surface and were
drawn off. A third oil was obtained by heating the liver-residues to
above the boiling-point of water, whereupon a black product, technically
called "brown oil," separated. The modern practice consists in heating
the perfectly fresh, cleaned livers by steam to a temperature above that
of boiling water, or, in more recent practice, to a lower temperature,
the livers being kept as far as possible from contact with air. The oils
so obtained are termed "steamed-liver oils." The "pale" and "light
brown" oils are used in pharmacy; the "brown" oil, the cod oil of
commerce, being obtained from putrid and decomposing livers, has an
objectionable taste and odour and is largely employed by tanners. By
boiling the livers at a somewhat high temperature, "unracked" cod oil is
obtained, containing a considerable quantity of "stearine"; this fat,
which separates on cooling, is sold as "fish stearine" for soap-making,
or as "fish-tallow" for currying. The oil when freed from the stearine
is known as "racked oil." "Coast cod oil" is the commercial name for the
oil obtained from the livers of various kinds of fish, _e.g._ hake,
ling, haddock, &c. The most important centres of the cod-liver oil
industry are Lofoten and Romsdal in Norway; the oil is also prepared in
the United States, Canada, Newfoundland, Iceland and Russia; and at one
time a considerable quantity was prepared in the Shetland Islands and
along the east coast of Scotland.
Cod-liver oil contains palmitin, stearin and other more complex
glycerides; the "stearine" mentioned above, however, contains very
little palmitin and stearin. Several other acids have been identified:
P. M. Meyerdahl obtained 4% of palmitic acid, 20% of jecoleic acid,
C19H36O2, and 20% of therapic acid, C17H26O2; other investigators have
recognized jecoric acid, C18H30O2, asellic acid, C17H32O2, and
physetoleic acid, C16H30O2, but some uncertainty attends these last
three acids. Therapic and jecoleic acids apparently do not occur
elsewhere in the animal kingdom, and it is probable that the therapeutic
properties of the oil are associated with the presence of these acids,
and not with the small amount of iodine present as was at one time
supposed. Other constituents are cholesterol (0.46-1.32%), traces of
calcium, magnesium, sodium, chlorine and bromine, and various aliphatic
amines which are really secondary products, being formed by the
decomposition of the cellular tissue.
Cod-liver oil is used externally in medicine when its internal
administration is rendered impossible by idiosyncrasy or the state of
the patient's digestion. The oil is very readily absorbed from the skin
and exerts all its therapeutic actions when thus exhibited. This method
is often resorted to in the case of infants or young children suffering
from abdominal or other forms of tuberculosis. Its only objection is the
odour which the patient exhales. When taken by the mouth, cod-liver oil
shares with other liver-oils the property of ready absorption. It often
causes unpleasant symptoms, which must always be dealt with and not
disregarded, more harm than good being done if this course is not
followed. Fortunately a tolerance is soon established in the majority of
cases. It has been experimentally proved that this is more readily
absorbed than any other oil--including other liver-oils. Much attention
has been paid to the explanation of this fact, since knowledge on this
point might enable an artificial product, without the disadvantages of
this oil, to be substituted for it. Very good results have been obtained
from a preparation named "lipanin," which consists of six parts of oleic
acid and ninety-four of pure olein. Cod-liver oil has the further
peculiarity of being more readily oxidizable than any other oil; an
obviously valuable property when it is remembered that the entire
food-value of oils depends on their oxidation.
Cod-liver oil may be given in all wasting diseases, and is occasionally
valuable in cases of chronic rheumatoid arthritis; but its great
therapeutic value is in cases of tuberculosis of whatever kind, and
notably in pulmonary tuberculosis or consumption. Its reputation in this
is quite inexpugnable. It is essential to remember that "in phthisis the
key of the situation is the state of the alimentary tract," and the
utmost care must be taken to obviate the nausea, loss of appetite and
diarrhoea, only too easily induced by this oil. It is best to begin with
only one dose in the twenty-four hours, to be taken just before going to
sleep, so that the patient is saved its unpleasant "repetition" from an
unaccustomed stomach. In general, it is therefore wise to order a double
dose at bedtime. The oil may be given in capsules, or in the form of an
emulsion, with or without malt-extract, or success may be obtained by
adding, to every two drachms of the oil, ten minims of pure ether and a
drop of peppermint oil. The usual dose, at starting, is one or two
drachms, but the oil should be given eventually in the largest
quantities that the patient can tolerate.
CODRINGTON, CHRISTOPHER (1668-1710), British soldier and colonial
governor, whose father was captain-general of the Leeward Isles, was
born in the island of Barbados, West Indies, in 1668. Educated at Christ
Church, Oxford, he was elected a fellow of All Souls, and subsequently
served with the British forces in Flanders, being rewarded in 1695 with
a captaincy in the Guards. In the same year he attended King William
III. on his visit to Oxford, and, in the absence of the public orator,
was chosen to deliver the University oration. In 1697, on the death of
his father, he was appointed captain-general and commander-in-chief of
the Leeward Isles. In 1703 he commanded the unsuccessful British
expedition against Guadeloupe. After this he resigned his governorship,
and spent the rest of his life in retirement and study on his Barbados
estates. He died on the 7th of April 1710, bequeathing these estates to
the Society for the Propagation of the Gospel in Foreign Parts for the
foundation of a college in Barbados. This college, known as the
Codrington college, was built in 1714-1742. To All Souls College,
Oxford, he bequeathed books worth L6000 and L10,000 in money, out of
which was built and endowed the Codrington library there.
CODRINGTON, SIR EDWARD (1770-1851), British admiral, belonged to a
family long settled at Dodington in Gloucestershire. He was the youngest
of three brothers, who were left orphans at an early age, and were
educated by an uncle, Mr Bethell. Edward Codrington was sent for a short
time to Harrow, and entered the navy in July 1783. He served on the
American station, in the Mediterranean and at home, till he was promoted
lieutenant on the 28th of May 1783. Lord Howe selected him to be signal
lieutenant on the flagship of the Channel fleet at the beginning of the
revolutionary war with France. In that capacity he served in the "Queen
Charlotte" (100) during the operations which culminated in the battle
of the 1st of June 1794. The notes he wrote on Barrow's account of the
battle in his _Life of Howe_, and the reminiscences he dictated to his
daughter, which are to be found in her memoir of him, are of great value
for the history of the action. On the 7th of October 1794 he was
promoted commander, and on the 6th of April 1795 attained the rank of
post-captain and the command of the "Babet" (22). He continued to serve
in the Channel, and was present at the action off L'Orient on the 23rd
of June 1795. Codrington wrote notes on this encounter also, which are
to be found in the memoir. They are able and valuable, but, like all his
correspondence throughout his life, show that he was of a somewhat
censorious disposition, was apt to take the worst view of the conduct of
others, and was liable to be querulous. He next commanded the "Druid"
(32) in the Channel and on the coast of Portugal, till she was paid off
in 1797. Codrington now remained on shore and on half-pay for some
years. In December 1802 he married Jane, daughter of Jasper Hall of
Kingston, Jamaica.
On the renewal of the war after the breach of the peace of Amiens he was
appointed (May 1805) to the command of the "Orion" (74) and was attached
to the fleet on the coast of Spain, then blockading Villeneuve in Cadiz.
The "Orion" took a conspicuous part in the battle of Trafalgar.
Codrington's correspondence contains much illuminative evidence as to
the preliminaries and the events of the victory. From 1805 till 1813 he
continued to serve first in the "Orion" and then (1808) in the "Blake"
(74) in European waters. He was present on the Walcheren expedition, and
was very actively employed on the Mediterranean coast of Spain in
co-operating with the Spaniards against the French. In 1814 he was
promoted rear-admiral, at which time he was serving on the coast of
North America as captain of the fleet to Sir Alexander Cochrane during
the operations against Washington, Baltimore and New Orleans. In 1815 he
was made K.C.B., and was promoted vice-admiral on the 10th of July 1821.
In December 1826 he was appointed to the Mediterranean command, and
sailed on the 1st of February 1827. From that date until his recall on
the 21st of June 1828 he was engaged in the arduous duties imposed on
him by the Greek War of Independence, which had led to anarchy and much
piracy in the Levant. On the 20th of October 1827 he destroyed the
Turkish and Egyptian naval forces at Navarino (q.v.), while in command
of a combined British, French and Russian fleet. As the battle had been
unforeseen in England, and its result was unwelcome to the ministry of
the day, Codrington was entangled in a correspondence to prove that he
had not gone beyond his instructions, and he was recalled by a despatch,
dated the 4th of June.
After the battle Codrington went to Malta to refit his ships. He
remained there till May 1828, when he sailed to join his French and
Russian colleagues on the coast of the Morea. They endeavoured to
enforce the evacuation of the peninsula by Ibrahim peacefully. The Pasha
made diplomatic difficulties, and on the 25th of July the three admirals
agreed that Codrington should go to Alexandria to obtain Ibrahim's
recall by his father Mehemet Ali. Codrington had heard on the 22nd of
June of his own supersession, but, as his successor had not arrived, he
carried out the arrangement made on the 25th of July, and his presence
at Alexandria led to the treaty of the 6th of August 1828, by which the
evacuation of the Morea was settled. His services were recognized by the
grant of the grand cross of the Bath, but there is no doubt that he was
treated as a scape-goat at least to some extent. After his return home
he was occupied for a time in defending himself, and then in leisure
abroad. He commanded a training squadron in the Channel in 1831 and
became admiral on the 10th of January 1837. From November 1839 to
December 1842 he was commander-in-chief at Portsmouth. He died on the
28th of April 1851.
Sir Edward Codrington left two sons, Sir William (1804-1884), a soldier
who commanded in the Crimea, and Sir John Henry (1808-1877), a naval
officer, who died an admiral of the fleet.
See _Memoir of the Life of Admiral Sir Edward Codrington_, by his
daughter Jane, Lady Bourchier, wife of Sir T. Bourchier, R.N. (London,
1873). (D. H.)
CODRUS, in Greek legend, the last king of Athens. According to the
story, it was prophesied at the time of the Dorian invasion of
Peloponnesus (_c._ 1068 B.C.) that only the death of their king at the
enemy's hands could ensure victory to the Athenians. Devoting himself to
his country, Codrus, in the disguise of a peasant, made his way into the
enemy's camp, and provoked a quarrel with some Dorian soldiers. He fell,
and the Dorians, on discovering that Codrus had been slain, retreated
homeward, despairing of success. No one being thought worthy to succeed
Codrus, the title of king was abolished, and that of archon (q.v.)
substituted for it.
See Lycurgus, _Leocr._ xx. [=84-87]; Justin ii. 6; Vell. Pat. i. 2;
Grote, _Hist. of Greece_, pt. i. ch. 18; Busolt, _Griechische
Geschichte_, i.
CODY, WILLIAM FREDERICK (1846- ), American scout and showman, known
under the name of "Buffalo Bill," was born in 1846 in Scott county,
Iowa. He first became known as one of the riders of the "Pony Express,"
a mail service established in the spring of 1860 by the Central Overland
California and Pike's Peak Express Company to carry the mails overland
from Saint Joseph, Missouri, to Sacramento, California, a distance of
1950 m., by means of relays of ponies, each rider being expected to
cover about 75 m. daily. Owing to the wildness of the country and the
hostility of the Indians, both the riders and the station-keepers led
lives of great hardship and danger. The "Pony Express" was discontinued
in 1861 upon the completion of the Pacific Telegraph company's line, and
young Cody became a scout and guide for the United States army. In 1863
he formally enlisted in the 7th regiment of Kansas cavalry, in which he
served until the close of the Civil War. In 1867 he made a contract with
the Kansas Pacific railway to furnish its employees with buffalo meat
while the line was being extended through the wilderness, and his name
of "Buffalo Bill" was given him from this circumstance. In 1868-1872 he
was again an army scout and guide, serving against the Sioux and
Cheyennes; and in 1872 was a member of the Nebraska house of
representatives. During the Sioux-Cheyenne War of 1876 he served in the
5th United States Cavalry, and at the battle of Indian Creek killed the
Cheyenne chief Yellow Hand in single combat. In 1883 he organized his
"Wild West Show," a spectacular performance on a large scale, his first
European tour taking place in 1887. In the Nebraska national guard he
again served against the Sioux in 1890-1891.
CO-EDUCATION, the term applied to the instruction and training of boys
and girls, or of young people of both sexes, in the same school or
institution, in the same classes and through the same courses of study.
Examples of the thoroughgoing application of this principle can be found
in every grade of education from the elementary school to the
university. But the term "Co-education" is sometimes used in a wider
sense, in order to include cases in which boys and girls, or young men
and young women of university age, are admitted to membership of the
same school or college but receive instruction wholly or in part in
separate classes and in different subjects. Other variable factors in
co-educational systems are the extent to which men and women are mixed
on the teaching staff, and the freedom of intercourse permitted between
pupils of the two sexes in class, in games and in other activities of
school life. In another form of combined education (preferred by Comte,
_Systeme de politique positive_, iv. 266), pupils of the two sexes are
taught successively by the same teacher. By the English Board of
Education, a distinction is drawn between mixed schools and dual
schools. "Mixed schools" are those in which, for most subjects of the
curriculum, boys and girls are taught together by the same teachers: in
"dual schools" there are separate boys' and girls' departments under a
single principal, but with separate entrances, classrooms and
playgrounds for the two sexes.
_History._--Co-education in early times was occasional and sporadic. For
example, women were admitted by Plato to the inner circle of the Academy
on terms of equality with men. The educational endowments of Teos
provided that the professors of literature should teach both boys and
girls. It is uncertain whether the Roman schools in classical times were
attended by both sexes. A tombstone found at Capua represents a
schoolmaster with a boy on one side and a girl on the other. Probably
co-education was practised in country districts for economical reasons;
and also in the home schools organized by wealthier families (Wilkins,
_Roman Education_, pp. 42-43). At Charles the Great's Palace School at
Aachen (A.D. 782 onwards), Alcuin taught together the young princes and
their sisters, as well as grown men and women. The Humanists of the
Renaissance made the full development of personality a chief aim of
education, and held up literary accomplishment as a desirable mark of
personal distinction both for men and women. This led to the scholarly
education of girls along with boys in the home schools of some great
families. Thus, at Mantua (1423 onwards), Vittorino da Feltre taught
Cecilia Gonzaga with her brothers and the other boy pupils at his
boarding-school; but there is no evidence that the latter was otherwise
co-educational. Luther and other Reformers urged that girls as well as
boys should be taught to read the Bible. Hence came the tendency to
co-education of boys and girls in some elementary schools in Protestant
lands. This tendency can be traced both in Scotland and in the northern
parts of England. It is believed that, in the early days of New England,
district schools in smaller American towns were open to boys and girls
alike, but that few girls advanced beyond reading and writing (Martin,
_Massachusetts Public School System_, p. 130). At Dorchester, Mass., it
was left to the discretion of the elders and schoolmen whether maids
should be taught with the boys or not; but in practice the girls seem to
have been educated apart. In 1602 the council of Ayr, Scotland, ordained
that the girls who were learning to read and write at the Grammar School
should be sent to the master of the Song School, "because it is not
seemly that sic lasses should be among the lads" (Grant, _History of the
Burgh and Parish Schools of Scotland_, p. 526 ff.). Meriden,
Connecticut, seems to have made common provision for the elementary
education of boys and girls in 1678. Northampton, Mass., did the same in
1680. Deerfield, Mass., in 1698 voted that "all families having children
either male or female between the ages of six and ten years shall pay by
the poll for their schooling"--presumably in the common school.
Thus the beginnings of co-education in its modern organized form may be
traced back partly to Scotland and partly to the United States. The
co-education of boys and girls, carried through in varying degrees of
completeness, was not uncommon in the old Endowed Schools of Scotland,
and became more frequent as increasing attention was given to the
education of girls. At the Dollar Institution, founded by John McNabb
for the benefit of the poor of the parish of Dollar and shire of
Clackmannan (date of will, 1800), boys and girls have been educated
together in certain classes since the beginning of the school in 1818.
In the eastern parts of the United States, where the Puritan tradition
also prevailed, co-education struck firm root, and spread chiefly for
reasons of convenience and economy (Dexter, _History of Education in
United States_, p. 430). But throughout the west, co-education was
strongly preferred in elementary and secondary schools and in
universities on the further ground that it was believed to be more in
accordance with the democratic principle of equal educational
opportunity for the two sexes.
It should be added, however, that the leaven of Pestalozzi's thought has
worked powerfully both in Europe and America in favour of the idea of
co-education. His view was that all educational institutions should, as
far as possible, be modelled upon the analogy of the family and of the
home. At Stanz (1798-1799) he educated together in one household boys
and girls ranging in age from five to fifteen. At Burgdorf (1799-1804)
his work was in part co-educational. At Yverdun (1804-1825) Pestalozzi
established a school for girls close to his school for boys. The girls
received instruction from some of the masters of the boys' school, and
girls and boys met at evening worship, in short excursions and at other
times.
In England, the Society of Friends have been the pioneers of
co-education in boarding schools, both for younger children and for
pupils up to fifteen or sixteen years of age. The practice of the
society, though not exclusively co-educational, has long been favourable
to co-education, either in its complete or restricted form, as being
more in harmony with the conditions of family life. Ackworth school was
established by the London Yearly Meeting in 1779 for the education of
boys and girls; but the school has never been fully co-educational, the
boys and girls being taught separately except in a few classes. At
Sidcot school, which was founded in 1808 by the Associated Quarterly
Meetings in the west of England for the education of children of
Friends, boys and girls are taught together, except in certain
handicraft subjects. Several other co-educational schools were founded
by the Society of Friends during the first half of the 19th century.
Since that time the movement towards co-education in secondary schools
and universities has steadily gained strength in England. It has been
furthered by the diffusion of Pestalozzian ideas and also by the
influence of American example. In England, private schools have made
some of the most valuable co-educational experiments. A private boarding
and day secondary school on co-educational lines was instituted by Mr W.
A. Case in Hampstead in 1865. A co-educational boarding-school was
founded in 1869 by Miss Lushington at Kingsley near Alton, Hants. In
1873 Mr W. H. Herford began the Ladybarn school for boys and girls at
Withington in the suburbs of Manchester. The passing of the Welsh
Intermediate Education Act 1889 led to the establishment of a
considerable number of new mixed or dual secondary day-schools in Wales.
Many English teachers gained experience in these schools and
subsequently influenced English education. The work and writings of Mr
J. H. Badley at Bedales, Petersfield, a co-educational boarding-school
of the first grade, gave greatly increased weight to the principle of
co-education. Important additions have also been made to the fund of
co-educational experience by the King Alfred's school (Hampstead),
Keswick school, and West Heath school (Hampstead). In 1907 a Public
Co-educational Boarding School was opened at Harpenden.
Since the Education Act 1902 became law, there has been a rapid increase
of co-educational secondary day-schools of the lower grade, under county
or borough education authorities, in all parts of England. This increase
is due to two chief causes, viz. (1) The co-educational tradition of
some of the higher grade board schools, many of which have become
secondary schools; and (2) the economy effected by establishing one
co-educational secondary school, in place of two smaller schools for
boys and girls separately.
The idea of co-education in secondary schools has spread in several
other European countries, especially in Holland, Norway, Sweden and
Denmark. In Scandinavia, the new practice appears to have begun with the
establishment of a private higher secondary school, the Palmgremska
Samskolan, in Stockholm, in 1876. A similar school, Nya Svenska
Laroverket, was founded upon the same model in Helsingfors, Finland, in
1880. In Norway, the law of 1896 introduced co-education in all state
schools. In Denmark, as in Norway, co-education was begun in private
schools; on its proving a success there, it was introduced into the
state schools, with two exceptions; and it is now obligatory in most
state schools but optional in private schools (J. S. Thornton, _Schools
Public and Private in the North of Europe_, 1907, p. 97). In Holland,
there is now a good deal of co-education in lower secondary schools of
the modern type. For example, at Utrecht, the state higher burgher
school provides the same course of instruction, except in gymnastics,
for boys and girls. At Almeloo, the municipal higher burgher school,
though co-educational, differentiates the classes in several subjects.
In Belgium, France, Germany and Austria, co-education, though frequent
in elementary schools, is regarded as undesirable in secondary; but the
movement in its favour in many parts of Germany seems to be gathering
strength. All over Europe the Roman Catholic populations prefer the
older ideal of separate schools for boys and girls.
Co-education in colleges and universities, which began at Oberlin, Ohio,
in 1833, was adopted almost without exception by the state universities
throughout the west of America from 1862 onwards. Since that time the
idea has spread rapidly throughout Europe, and the presence of women
students at universities originally confined to men is one of the most
striking educational facts of the age.
_Co-education in the United Kingdom, (a) England and Wales._--The Board
of Education does not possess any summary showing the number of pupils
in mixed public elementary schools or in mixed departments of such
schools. In 1901, out of 31,502 departments of public elementary schools
in England and Wales, nearly half (15,504) were mixed departments, in
which boys and girls were educated together. But as the departments were
of unequal size, it must not be inferred from this that half the
children in public elementary schools in that year (5,883,762) were
receiving co-education. Of the total number of departments in public
elementary schools in England and Wales, the percentage of mixed schools
fell from 51.6 in 1881 to 49.4 in 1891 and 49.2 in 1901. But these
percentages must not be taken to prove an absolute decline in the number
of children in mixed departments.
In England, out of 492 public secondary schools which were recognized by
the Board of Education for the receipt of government grant for the
school year ending July 31, 1905, and which contained 85,358 pupils, 108
schools, with 21,720 pupils, were mixed; and 20 schools, with 8980
pupils, were dual schools.
Thus, of the total number of pupils in the secondary schools referred to
above, a little over 25% were in mixed schools, and about 10% were in
dual schools. It is not safe to assume, however, that all the mixed
schools were completely co-educational in their work, or that the dual
schools were not co-educational in respect of certain subjects or parts
of the course. It should also be remembered that, besides the secondary
schools recognized by the Board of Education for the receipt of
government grant, there is a considerable number of great endowed
secondary boarding-schools ("public schools" in the English use of that
expression) which are for boys only. There are also at least 5000
private secondary schools, of which, in 1897 (since when no
comprehensive statistical inquiry has been made), 970, with 26,027
pupils, were mixed schools. But the great majority of the children in
these mixed schools were under twelve years of age. The number of boys
and girls over twelve years of age, in the mixed private secondary
schools which were included in the 1897 return, was only 5488.
In Wales, for the school year ending July 31, 1905, out of 84
state-aided public secondary schools, 11 were mixed and 44 were dual
schools. The number of scholars in the Welsh schools referred to above
was 9340. Of these, 1457, or 15%, were in mixed schools, and 5085, or
54%, were in dual schools. The managers of dual schools in Wales have
the power to arrange that boys and girls shall be taught together in any
or all the classes; and, as a matter of fact, nearly all the dual
schools are worked as mixed schools, though they appear in these figures
under dual.
_(b) Scotland._--In the public elementary schools, including the higher
grade schools of Scotland, co-education is the almost universal rule.
The exceptions, which for the most part are Roman Catholic or Episcopal
Church schools, tend to diminish year by year. In 1905, out of 3843
departments in the Scotch public elementary and higher grade schools,
3783 were mixed. These include the infant departments. Out of the total
number of children in the public elementary and higher grade schools,
including infants' departments, 98.43% were receiving co-education.
In the secondary schools of Scotland there has been in recent years
little perceptible movement either towards co-education or away from it.
What movement there is, favours the establishment of separate secondary
schools for girls in the large centres of population. Out of 109 public
secondary schools in Scotland in 1905-1906, 29 schools were for boys
only and 40 schools for girls only. One school had boys and girls in
separate departments. In the remaining 39 schools, boys and girls were
taken together to an extent which varied with the subjects taken; but
there was nothing of the nature of a strict separation of the sexes as
regards the ordinary work of the school.
_(c) Ireland._--In Ireland, the percentage of pupils on the rolls of
mixed national schools (_i.e._ schools attended by boys and girls), to
the total number of pupils on the rolls of all national schools, has
slowly increased. In 1880 the percentage was 57.5; in 1898, 59.4; in
1905, 60.9.
The Commissioners of Intermediate Education in Ireland had on their list
in 1906, 38 secondary schools which were classified by them as mixed
schools. These schools were attended by 640 boys and 413 girls between
13 and 19 years of age. The commissioners do not know to what extent the
boys and girls in these schools received instruction in the same
classes. As, however, the schools are small, they believe that in the
great majority of cases the boys and girls were taught together. In one
large school not classified as mixed, the boys (117) and girls (60) were
taught in the same classes.
_Universities and University Colleges in the United Kingdom._--Women are
admitted as members of the universities of London, Durham, Manchester,
Liverpool, Birmingham, Leeds, Sheffield, Wales, Edinburgh, Aberdeen, St
Andrews, Glasgow, Dublin and the Royal University of Ireland. At Oxford
and Cambridge women are not admitted as members of the university, but
by courtesy enjoy entrance to practically all university lectures and
examinations. The social life of the men and women students is more
separate in the old than in the new universities. In no grade of
education in the United Kingdom has the principle of co-education made
more rapid advance than in the universities. The university education of
women began in London (Queen's College 1848, Bedford College 1849, both
being preceded by classes in earlier years). The University of London in
1878 decided to accept from the crown a supplemental charter making
every degree, honour and prize awarded by the university accessible to
students of both sexes on perfectly equal terms. By charter in 1880, the
Victoria University (now broken up into the universities of Manchester,
Liverpool and Leeds) received power to grant degrees to women as well as
to men. The charter of the university of Wales (1893) provides that
"Women shall be eligible equally with men for admittance to any degree
which our university is authorized to confer; every office created in
the university, and the membership of every authority constituted by the
charter shall be open to women equally with men." In 1889 the
Universities (Scotland) Act empowered the commissioners to make
ordinances, enabling each university to admit women in graduation in one
or more faculties and to provide for their instruction. At all the
university colleges in the United Kingdom women are educated as well as
men.
_United States._--Co-education is a characteristic feature of the
educational system of the different states of the American Union. Of
elementary school pupils at least 96%, and of secondary school pupils
95%, are in mixed schools. In 1903, out of a total enrolment of
15,990,803 pupils in public elementary and secondary schools and
training colleges, 15,387,734 were in schools attended by pupils of both
sexes. Out of 550,600 pupils on the rolls of public secondary schools
(high schools) in 1902, 523,300 were in co-educational schools. The same
was true of 43% of the pupils (numbering over 100,000) in private
secondary schools. In colleges and universities 62% of all
undergraduates were in co-educational institutions, to which category
thirty-four American universities belong (U.S. Commissioner of
Education, _Report for 1903_, p. 2454). In America opinion is thus
predominantly in favour of co-education, but there is a current of
adverse criticism, especially among some who have had experience of
school conditions in large cities.
_General Review of the Question._--In schools for infants and younger
children co-education is approved by all authorities. It is increasingly
favoured on educational grounds in smaller schools for children up to 12
or 13 years of age or thereabouts. But where elementary schools have to
be large, separate departments for boys and girls are generally
preferable, though mixed schools are often established for reasons of
economy. At the other end of the educational scale, viz. in the
universities, the co-education of men and women in the same institution
is fast becoming the rule. This is due partly to the prohibitive cost of
duplicating teaching staff, laboratories, libraries and other equipment,
partly to the desire of women to qualify themselves for professional
life by passing through the same courses of training as are prescribed
for men. The degree, however, to which social intercourse is carried on
between men and women students differs widely in the different
co-educational universities. There are occasional signs, _e.g._ at
Chicago, of a reaction against the fullest form of academic
co-education. And it is probable that the universities will provide,
among many courses common to men and women, some (like engineering)
suitable for men only, and others (like advanced instruction in
home-science, or certain courses of professional preparation for
teachers of young children) which will rarely be attended by any but
women. Common use of the same university institutions is compatible with
much differentiation in courses of study and with separately organized
forms of collegiate life. It is with regard to the part of education
which lies between the elementary schools and the universities that the
sharpest division of opinion upon the principle of co-education now
exists. In Europe, with the exception of Scandinavia, those who advocate
co-education of the sexes in secondary schools up to 18 or 19 years of
age are at present in a distinct minority, even as regards day schools,
and still more when they propose to apply the same principle to boarding
schools. But the application of the co-educational principle to all
schools alike is favoured by an apparently increasing number of men and
women. This movement in opinion is connected with the increase in the
number of girls desiring access to secondary schools, a demand which can
most easily and economically be met by granting to girls access to some
of the existing schools for boys. The co-educational movement is also
connected with a strong view of sex equality. It is furthered by the
rapidly increasing number of women teachers who are available for higher
educational work. Mixed secondary schools with mixed staffs are
spreading for reasons of economy in smaller towns and rural districts.
In large towns separate schools are usually recommended in preference,
but much depends upon the social tradition of the neighbourhood. Those
who advocate co-education for boys and girls in secondary schools urge
it mainly on the ground of its naturalness and closer conformity to the
conditions of healthy, unselfconscious home life. They believe it to be
a protective against uncleanness of talk and school immorality. They
point to its convenience and economy. They welcome co-education as
likely to bring with it a healthy radicalism in regard to the older
tradition of studies in boys' secondary schools. They approve it as
leading to mixed staffs of men and women teachers, and as the most
effectual way of putting girls in a position of reasonable equality with
boys in respect of intellectual and civic opportunity. On the other
hand, those who oppose co-education in secondary schools rest their case
upon the danger of the intellectual or physical overstrain of girls
during adolescence; and upon the unequal rate of development of boys and
girls during the secondary school period, the girls being more forward
than the boys at first, but as a rule less able to work as hard at a
somewhat later stage. The critics further complain that co-education is
generally so organized that the girls' course of study is more or less
assimilated to that of the boys, with the result that it cannot have the
artistic and domestic character which is suitable for the majority of
girls. Complaint is also made that the head of a co-educational school
for pupils over the age of 10 is usually a man, though the health and
character of girls need the care and control of a woman vested with
complete authority and responsibility. While demurring to the view that
co-education of the sexes would be a moral panacea, the critics of the
system admit that the presence of the girls would exert a refining
influence, but they believe that on the whole the boys are likely to
gain less from co-education than the girls are likely to lose by it. In
all these matters carefully recorded observation and experiment are
needed, and it may well be found that co-education is best for some boys
and for some girls, though not for all. Temperaments and dispositions
differ. Some boys seem by nature more fitted for the kind of training
generally given to girls; some girls are by nature fitted for the kind
of training generally given to boys. The sex division does not mark off
temperaments into two sharply contrasted groups. The introduction of
girls into boys' secondary schools may remove or mitigate coarse
traditions of speech and conduct where such persist. But it would be
unfortunate if stiff and pedantic traditions of secondary education were
now fixed upon girls instead of being reconsidered and modified in the
interests of boys also. In any case, if co-education in secondary
schools is to yield the benefits which some anticipate from it, great
vigilance, careful selection of pupils and very liberal staffing will be
necessary. Without these securities the results of co-education in
secondary schools might be disappointing, disquieting or even
disastrous.
BIBLIOGRAPHY.--Plato in the _Republic_ (v. 452-456) and _Laws_ (vii.
804-805) argues that women should share as far as possible in
education with men. Mary Wollstonecraft, _A Vindication of the Rights
of Women_ (1792), contends that "both sexes ought, not only in private
families but in public schools, to be educated together." J. G.
Spurzheim, _Principles of Education_, pp. 272-288 (Edinburgh, 1821),
replies to this argument. In the Board of Education _Special Reports
on Educational Subjects_, vol. vi. (Wyman & Sons, 1900), J. H. Badley,
writing on _The Possibility of Co-education in English Preparatory and
other Secondary Schools_, is strongly in favour. "In co-education ...
half-heartedness means failure. The more completely both sexes can be
brought together upon an equal and natural footing the less the
difficulties grow." In the Board of Education _Special Reports_, vol.
xi. (Wyman & Sons, 1902), Rev. Cecil Grant, writing on _Can American
Education be grafted upon the English Public School System?_ answers
strongly in the affirmative; co-education is recommended on eight
grounds:--(1) Vast economy of expenditure; (2) return to the natural
system; (3) discipline made easier; (4) intellectual stimulus; (5) a
better balance in instruction; (6) improved manners; (7) prevention of
extremes of masculinity or femininity; (8) a safeguard against the
moral danger.
_Co-education: a series of Essays_ (London, 1903), edited by Alice
Woods, is in favour of co-education, nine practical workers recording
their experience; this is one of the best books on the subject. J. H.
Badley's _Co-education after Fifteen: its Value and Difficulties_.
_Child Life_ (London, January, 1906), is candid, judicious and
practical. M. E. Sadler in _Reports on Secondary Education in
Hampshire, Derbyshire and Essex_ (1904, 1905 and 1906 respectively)
gives details of the curriculum of many co-educational secondary
schools. In the U.S. Commissioner of Education _Report for 1903_, vol.
i. pp. 1047-1078, Anna Tolman Smith, writing on _Co-education in the
Schools and Colleges of the United States_, gives an historical review
of the subject with bibliography (compare bibliography in _Report of
U.S. Commissioner of Education for 1900-1901_, pp. 1310-1325). G.
Stanley Hall on _Adolescence, its Psychology and its Relations to
Physiology, Anthropology, Sociology, Sex, Crime, Religion and
Education_, vol. ii. chap. xvii., on Adolescent Girls and their
education (New York, D. Appleton & Co., 1904), is strongly against
co-education during adolescence. In W. Rein's _Encyklopadisches
Handbuch der Padagogik_ (Langensalza, Beyer), art. "Gemeinsame
Erziehung fur Knaben und Madchen," K. E. Palmgren is in favour of
co-education (vol. iii. of 2nd ed. 1905). See also W. Rein, _Uber
gemeinsame Erziehung von Knaben und Madchen_ (Freiburg, 1903), and
_Bericht uber den I. Internationalen Kongress fur Schulhygiene_
(Nurnberg, 1904), vol. ii. pp. 140 ff., "Co-education in der hoheren
Schulen." (M. E. S.)
COEFFETEAU, NICOLAS (1574-1623), French theologian, poet and historian,
was born at Saint-Calais. He entered the Dominican order and lectured on
philosophy at Paris, being also "ordinary preacher" to Henry IV., and
afterwards ambassador at Rome. In 1606 he was vicar-general of the
congregation of France, and received from Marie de' Medici the revenues
of the sees of Lombez and Saintes. He also administered the diocese of
Metz, and was nominated to that of Marseilles in 1621, but ill-health
obliged him here to take a coadjutor. Coeffeteau won considerable
distinction in the controversy against the Protestant reformers and also
wrote a _History of Rome from Augustus to Constantine_. Many of his
theological writings were collected in one volume (Paris, 1622), and at
the time of his death in 1623 he was engaged on a translation of the New
Testament which is still in manuscript.
COEHOORN, MENNO, BARON VAN (1641-1704), Dutch soldier and military
engineer, of Swedish extraction, was born at Leeuwarden in Friesland. He
received an excellent military and general education, and at the age of
sixteen became a captain in the Dutch army. He took part in the defence
of Maastricht in 1673 and in the siege of Grave in the same year, where
the small mortars (called coehorns) invented by him caused the French
garrison considerable trouble (Seydel, _Nachrichten uber
Festungskriege_, Leipzig, 1818). He was made a colonel for his gallant
conduct at the battle of Seneff (1674), and was present also at the
battles of Cassel (1677) and Saint Denis (1678).
The circumstances of the time and the country turned Coehoorn's
attention to the art of fortification, and the events of the late war
showed him that existing methods could no longer be relied upon. His
first published work, _Versterckinge de Vijfhoeks met alle syne
Buytenwerken_ (Leeuwarden, 1682), at once aroused attention, and
involved the author in a lively controversy with a rival engineer, Louys
Paan (Leeuwarden, 1682, 1683; copies are in the library of the Dutch
ministry of war). The military authorities were much interested in this,
and entrusted Coehoorn with the reconstruction of several fortresses in
the Netherlands. This task he continued throughout his career; and his
experience in the work made him the worthy rival of his great
contemporary Vauban. He formulated his ideas a little later in his chief
work, _Nieuwe Vestingbouw op en natte of lage horizont_, &c.
(Leeuwarden, 1685), in which he laid down three "systems," the
characteristic feature of which was the multiplicity and great saliency
of the works, which were calculated and in principle are still eminently
suited for flat and almost marshy sites such as those of the Low
Countries. He borrowed many of the details from the works of his Dutch
predecessor Freytag, of Albrecht Durer, and of the German engineer
Speckle, and in general he aimed rather at the adaptation of his
principles to the requirements of individual sites than at producing a
geometrically and theoretically perfect fortress; and throughout his
career he never hesitated to depart from his own rules in dealing with
exceptional cases, such as that of Groningen. Subsequent editions of
_Nieuwe Vestingbouw_ appeared in Dutch (1702, and frequently
afterwards), English (London, 1705), French (Wesel, 1705), and German
(Dusseldorf, 1709).
From 1688 to the treaty of Ryswick Coehoorn served as a brigadier. At
the battle of Fleurus he greatly distinguished himself, and in 1692 he
defended Namur, a fortress of his own creation. Namur was taken by
Vauban; but the Dutch engineer had his revenge three years later, when
the place, on which in the meantime Vauban had lavished his skill, fell
to his attack. Coehoorn became lieutenant-general and inspector-general
of the Netherlands fortresses, and the high-German peoples as well as
his own countrymen honoured him. He commanded a corps in the army of the
duke of Marlborough from 1701 to 1703, and in the constant siege warfare
of these campaigns in the Low Countries his technical skill was of the
highest value. The swift reduction of the fortress of Bonn and the siege
of Huy in 1703 were his crowning successes. At the opening of his
following campaign he was on his way to confer with Marlborough when he
died of apoplexy at Wijkel on the 17th of March 1704.
His "first system" was applied to numerous places in Holland, notably
Nijmwegen, Breda and Bergen-op-Zoom. Mannheim in Germany was also
fortified in this way, while the "secondsystem" was applied to Belgrade
and Temesvar in eastern Europe.
His son, Gosewijn Theodor van Coehoorn, wrote his life (re-edited
Syperstein, Leeuwarden, 1860). See also v. Zastrow, _Geschichte der
bestandigen Befestigung_ (Leipzig, 1828); von Brese-Winiari, _Uber
Entstehen und Wesen der neueren Befestigungsmethode_ (1844); Cosseran
de Villenoisy, _Essai historique sur la fortification_ (1869); Mandar,
_Architecture des forteresses_ (1801); Krayenhoff, _Verhandeling over
de erste versterkingsmanier van Coehoorn_ (Hague, 1823); Bosscha,
_Nederlandsche heldend te Land_ (Amsterdam, 1838); Dewez, _Histoire de
Belgique_ (Brussels, 1823); Ypey, _Narratio de rebus gestis Mennonis
Cohorni_ (1771); Hennert, _Dissertation sur la fortification
permanente_ (1795); Bohms, _Grundliche Anleitung zur Kriegsbaukunst_
(1776); _Axiomatas of allgemeene bekentnisse over de Vestinghbouw door
Menno Baron van Coehoorn, Uytgewerkt door E. W. Berg_ (MS. in Dutch
Ministry of War); Bousmard, _Essai general de fortification_ (1797);
also the article FORTIFICATION AND SIEGECRAFT.
COELENTERA, a group or grade of the animal kingdom, the zoological
importance of which has risen considerably since the time (1887) of the
publication of the first article under that heading in the _Ency. Brit._
(9th edit.), even though their numbers have been reduced by the
elevation of the Sponges or Porifera to the rank of an independent
Phylum under the title Parazoa (W. J. Sollas, 1884). For the Coelentera
thus restricted, the term Enterocoela, in contrast to Coelomocoela (the
old Coelomata), was suggested by E. R. Lankester (1900).
From the more complex colonial Protozoa the Coelentera are readily
separated by their possession of two distinct sets of cells, with
diverse functions, arranged in two definite layers,--a condition found
in no Protozoan. The old criterion by which they and other Metazoa were
once distinguished from Protozoa, namely, the differentiation of large
and small sexual cells from each other and from the remaining cells of
the body, has been broken down by the discovery of numerous cases of
such differentiation among Protozoa. The Coelentera, as contrasted with
other Metazoa (but not Parazoa), consist of two layers of cells only, an
outer layer or ectoderm, an inner layer or endoderm. They have hence
been described as Diploblastica. In the remaining Metazoa certain cells
are budded off at an early stage of development from one or both of the
two original layers, to form later a third layer, the mesoderm, which
lies between the ectoderm and endoderm; such forms have therefore
received the name Triploblastica. At the same time it is necessary to
observe that it is by no means certain that the mesoderm found in
various groups of Metazoa is a similar or homologous formation in all
cases. A second essential difference between Coelentera and other
Metazoa (except Parazoa) is that in the former all spaces in the
interior of the body are referable to a single cavity of endodermal
origin, the "gastro-vascular cavity," often termed the coelenteron: the
spaces are always originally continuous with one another, and are in
almost every case permanently so. This single cavity and its lining
serve apparently for all those functions (digestion, excretion,
circulation and often reproduction) which in more complex organisms are
distributed among various cavities of independent and often very diverse
origin.
In the Coelentera the ectoderm and endoderm are set apart from one
another at a very early period in the life-history; generally either by
delamination or invagination, processes described in the article
EMBRYOLOGY. Between these two cell-layers a mesogloea (G. C. Bourne,
1887) is always intercalated as a secretion by one or both of them; this
is a gelatinoid, primitively structureless lamella, which in the first
instance serves merely as a basal support for the cells. In many cases,
as, for example, in the Medusae or jelly-fish, the mesogloea may be so
thick as to constitute the chief part of the body in bulk and weight.
The ectoderm rarely consists of more than one layer of cells: these are
divisible by structure and function into nervous, muscular and secretory
cells, supported by interstitial cells. The endoderm is generally also
an epithelium one cell in thickness, the cells being digestive,
secretory and sometimes muscular. Reproductive sexual cells may be found
in either of these two layers, according to the class and sub-class in
question. The mesogloea is in itself an inert non-cellular secretion,
but the immigration of muscular and other cells into its substance, from
both ectoderm and endoderm, gives it in many cases a strong resemblance
to the mesoderm of Triploblastica,--a resemblance which, while probably
superficial, may yet serve to indicate the path of evolution of the
mesoderm.
The Coelentera may thus be briefly defined as Metazoa which exhibit two
embryonic cell-layers only,--the ectoderm and endoderm,--their
body-cavities being referable to a single cavity or coelenteron in the
endoderm. Their position in the animal kingdom and their main
subdivisions may be expressed in the following table:--
I. PROTOZOA.
II. PARAZOA or PORIFERA.
III. METAZOA.
|
+----------+--------------+
| |
Coelentera Triploblastica
= Diploblastica. (including Coelomata).
|
+------+-----------+-----------------+
| | |
Hydromedusae. Scyphozoa. Ctenophora.
|
+--------+----------+
| |
Scyphomedusae. Anthozoa.
In the above-given classification, the Scyphomedusae, formerly included
with the Hydromedusae as Hydrozoa, are placed nearer the Anthozoa. The
reasons for this may be stated briefly.
The HYDROMEDUSAE are distinguished from the Scyphozoa chiefly by
negative characters; they have no stomodaeum, that is, no ingrowth of
ectoderm at the mouth to form an oesophagus; they have no mesenteries
(radiating partitions) which incompletely subdivide the coelenteron; and
they have no concentration of digestive cells into special organs. Their
ectodermal muscles are mainly longitudinal, their endodermal muscles are
circularly arranged on the body-wall. Their sexual cells are (probably
in all cases) produced from the ectoderm, and lie in those radii which
are first accentuated in development. They typically present two
structural forms, the non-sexual hydroid and the sexual medusoid; in
such a case there is an alternation of generations (metagenesis), the
hydroid giving rise to the medusoid by a sexual gemmation, the medusoid
bearing sexual cells which develop into a hydroid. In some other cases
medusoid develops directly from medusoid (hypogenesis), whether by
sexual cells or by gemmation. The medusoids have a muscular velum of
ectoderm and mesogloea only.
The SCYPHOZOA have the following features in common:--They typically
exhibit an ectodermal stomodaeum; partitions or mesenteries project into
their coelenteron from the body-wall, and on these are generally
concentrated digestive cells (to form mesenterial filaments, phacellae
or gastric filaments, &c.); the external musculature of the body-wall is
circular (except in _Cerianthus_); the internal, longitudinal; and the
sexual cells probably always arise in the endoderm.
The SCYPHOMEDUSAE, like the Hydromedusae, typically present a
metagenesis, the non-sexual scyphistomoid (corresponding to the hydroid)
alternating with the sexual medusoid. In other cases the medusoid is
hypogenetic, medusoid producing medusoid. The sexual cells of the
medusoid lie in the endoderm on interradii, that is, on the second set
of radii accentuated in the course of development. The medusoids have no
true velum; in some cases a structure more or less resembling this
organ, termed a velarium, is present, permeated by endodermal canals.
The ANTHOZOA differ from the Scyphomedusae in having no medusoid form;
they all more or less resemble a sea-anemone, and may be termed
actinioid. They are (with rare exceptions, probably secondarily
acquired) hypogenetic, the offspring resembling the parent, and both
being sexual. The sexual cells are borne on the mesenteries in positions
irrespective of obvious developmental radii.
The CTENOPHORA are so aberrant in structure that it has been proposed to
separate them from the Coelentera altogether: they are, however,
theoretically deducible from an ancestor common to other Coelentera, but
their extreme specialization precludes the idea of any close
relationship with the rest.
As regards the other three groups, however, it is easy to conceive of
them as derived from an ancestor, represented to-day to some extent by
the planula-larva, which was Coelenterate in so far as it was composed
of an ectoderm and endoderm, and had an internal digestive cavity (I. of
the table).
At the point of divergence between Scyphozoa and Hydromedusae (II. of
the table of hypothetical descent), we may conceive of its descendant as
tentaculate, capable of either floating (swimming) or fixation at will
like Lucernaria to-day; and exhibiting incipient differentiation of
myoepithelial cells (formerly termed neuro-muscular cells). At the
parting of the ways which led, on the one hand, to modern Scyphomedusae,
on the other to Anthozoa (III.), it is probable that the common ancestor
was marked by incipient mesenteries and by the limitation of the sexual
cells to endoderm. The lines of descent--II. to Hydromedusae, and III.
to Scyphomedusae--represent periods during which the hypothetical
ancestors II. and III., capable of either locomotion or fixation at
will, were either differentiated into alternating generations of fixed
sterile nutritive hydroids (scyphistomoids) and locomotor sexual
medusoids, or abandoned the power of fixation in hypogenetic cases.
During the period represented by the line of descent--III. to
Anthozoa--this group abandoned its power of adult locomotion by
swimming. During these periods were also attained those less important
structural characters which these three groups present to-day.
(G. H. Fo.)
Hydromedusae. Scyphomedusae. Anthozoa.
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\ III.
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Ctenophora? \ /
\ II.
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I.
COELLO, ALONSO SANCHEZ (1515-1590), Spanish painter, according to some
authorities a native of Portugal, was born, according to others, at
Benifacio, near the city of Valencia. He studied many years in Italy;
and returning to Spain in 1541 he settled at Madrid, and worked on
religious themes for most of the palaces and larger churches. He was a
follower of Titian, and, like him, excelled in portraits and single
figures, elaborating the textures of his armours, draperies, and such
accessories in a manner so masterly as strongly to influence Velazquez
in his treatment of like objects. Many of his pictures were destroyed in
the fires that consumed the Madrid and Prado palaces, but many good
examples are yet extant, among which may be noted the portraits of the
infantes Carlos and Isabella, now in the Madrid gallery, and the St
Sebastian painted in the church of San Geronimo, also in Madrid. Coello
left a daughter, Isabella Sanchez, who studied under him, and painted
excellent portraits.
COELLO, ANTONIO (1610?-1652), Spanish dramatist and poet, was born at
Madrid about the beginning of the 17th century. He entered the household
of the duke de Albuquerque, and after some years of service in the army
received the order of Santiago in 1648. He was a favourite of Philip
IV., who is reported to have collaborated with him; this rumour is not
confirmed, but there is ample proof of Coello's collaboration with
Calderon, Rojas Zorrilla, Solis and Velez de Guevara, the most
distinguished dramatists of the age. The best of his original plays,
_Los Empenos de seis horas_, has been wrongly ascribed to Calderon; it
was adapted by Samuel Tuke, under the title of _The Adventures of five
Hours_, and was described by Pepys as superior to _Othello_. It is an
excellent example of stagecraft and animated dialogue. Coello died on
the 20th of October 1652, shortly after his nomination to a post in the
household of Philip IV.
COELOM AND SEROUS MEMBRANES. In human anatomy the body-cavity or coelom
(Gr. [Greek: koilos], hollow) is divided into the _pericardium_, the two
_pleurae_, the _peritoneum_ and the two _tunicae vaginales_.
The _pericardium_ is a closed sac which occupies the central part of the
thorax and contains the heart. Like all the serous membranes it has a
visceral and a parietal layer, the former of which is closely applied to
the heart and consists of endothelial cells with a slight fibrous
backing: to it is due the glossy appearance of a freshly removed heart.
The parietal layer is double; externally there is a strong fibrous
protective coat which is continuous with the other fibrous structures in
the neighbourhood, especially with the sheaths of the great vessels at
the root of the heart, with prolongations of the fascia of the neck, and
with the central tendon of the diaphragm, while internally is the serous
layer which is reflected from the surface of the heart, where the great
vessels enter, so that everywhere the two layers of the serous membrane
are in contact, and the only thing within the cavity is a drop or two of
the fluid secreted by the serous walls. When the parietal layer is laid
open and the heart removed by cutting through the great vessels, it will
be seen that there are two lines of reflection of the serous layer, one
common to the aorta and pulmonary artery, the other to all the pulmonary
veins and the two venae cavae.
The _pleurae_ very closely resemble the pericardium except that the
fibrous outer coat of the parietal layer is not nearly as strong; it is
closely attached to the inner surface of the chest walls and mesially to
the outer layer of the pericardium; above it is thickened by a fibrous
contribution from the scalene muscles, and this forms the _dome of the
pleura_ which fits into the concavity of the first rib and contains the
apex of the lung. The reflection of the serous layer of the pleura, from
the parietal to the visceral part, takes place at the root of the lung,
where the great vessels enter, and continues for some distance below
this as the _ligamentum latum pulmonis_. The upper limit of the pleural
cavity reaches about half an inch above the inner third of the clavicle,
while, below, it may be marked out by a line drawn from the twelfth
thoracic spine to the tenth rib in the mid axillary line, the eighth rib
in the nipple line, and the sixth rib at its junction with the sternum.
There is probably very little difference in the lower level of the
pleurae on the two sides.
[Illustration: FIG. 1.--Diagram of vertical median section of Abdomen.
A, Aorta. D, Duodenum.
P, Pancreas. B, Bladder.
I, Intestine. St, Stomach.
R, Rectum. C, Colon.
L, Liver. V, Vagina.
(The fine dots represent the great sac of the peritoneum, the coarse
dots the lesser sac.)]
The _peritoneum_ is a more extensive and complicated membrane than
either the pericardium or pleura; it surrounds the abdominal and pelvic
viscera, and, like the other sacs, has a parietal and visceral layer.
The line of reflection of these, though a continuous one, is very
tortuous. The peritoneum consists of a _greater_ and _lesser sac_ which
communicate through an opening known as the _foramen of Winslow_, and
the most satisfactory way of understanding these is to follow the
reflections first in a vertical median (sagittal) section and then in a
horizontal one, the body being supposed to be in the upright position.
If a median sagittal section be studied first, and a start be made at
the umbilicus (see fig. 1), the parietal peritoneum is seen to run
upward, lining the anterior abdominal wall, and then to pass along the
under surface of the diaphragm till its posterior third is reached; here
there is a reflection on to the liver (L), forming the anterior layer of
the _coronary ligament_ of that viscus, while the membrane now becomes
visceral and envelops the front of the liver as far back as the
transverse fissure on its lower surface; here it is reflected on to the
stomach (St) forming the anterior layer of the _gastro-hepatic_ or
_lesser omentum_. It now covers the front of the stomach, and at the
lower border runs down as the anterior layer of an apron-like fold, the
_great omentum_, which in some cases reaches as low as the pubes; then
it turns up again as the posterior or fourth layer of the great omentum
until the transverse colon (C) is reached, the posterior surface of
which it covers and is reflected, as the posterior layer of the
_transverse meso-colon_, to the lower part of the pancreas (P); after
this it turns down and covers the anterior surface of the third part of
the duodenum (D) till the posterior wall of the abdomen is reached, from
which it is reflected on to the small intestine (I) as the anterior
layer of the _mesentery_, a fold varying from 5 to 8 in. between its
attachments. After surrounding the small intestine it becomes the
posterior layer of the mesentery and so again reaches the posterior
abdominal wall, down which it runs until the rectum (R) is reached. The
anterior surface of this tube is covered by peritoneum to a point about
3 in. from the anus, where it is reflected on to the uterus and vagina
(V) in the female and then on to the bladder (B); in the male, on the
other hand, the reflection is directly from the rectum to the bladder.
At the apex of the bladder, after covering the upper surface of that
organ, it is lifted off by the urachus and runs up the anterior
abdominal wall to the umbilicus, from which the start was made. All this
is the greater sac. The tracing of the lesser sac may be conveniently
started at the transverse fissure of the liver, whence the membrane runs
down to the stomach (St) as the posterior layer of the lesser omentum,
lines the posterior surface of the stomach, passes down as the second
layer of the great omentum and up again as the third layer, covers the
anterior surface of the transverse colon (C) and then reaches the
pancreas (P) as the anterior layer of the transverse mesocolon. After
this it covers the front of the pancreas and in the middle line of the
body runs up below the diaphragm to within an inch of the anterior layer
of the coronary ligament of the liver; here it is reflected on to the
top of the Spigelian lobe of the liver to form the posterior layer of
the coronary ligament, covers the whole Spigelian lobe, and so reaches
the transverse fissure, the starting-point.
[Illustration: FIG. 2.--Diagram of Horizontal Section through upper part
of 1st Lumbar Vertebra.
A, Aorta. H.A, Hepatic Artery.
Sp, Spleen. K, Kidney.
B.D, Bile duct. L, Liver.
V.C, Vena Cava. St, Stomach.
P, Pancreas. P.V, Portal Vein.