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near the hand of Hercules, was named Cerberus, by Hevelius.

CERCARIA-CEREALIA.

in the Parisian menagerie, was remarkable not only for the cunning and adroitness with which it searched and rifled the pockets of visitors, but also for the readiness with which it applied a key to the opening of a lock, untied knots, undid the rings of a chain, In the form to and performed other similar feats.

CERCA'RIA, a name formerly given to a supposed genus of Entozoa, at first, from their minute size, mistaken for Infusoria, but now known to be the young of Trematode Worms. which the name C. was given, these creatures consist of an oval body with a thread-like tail; and swim about with great activity in water, but exhibit a strong instinctive propensity to penetrate into the soft bodies of insect larvæ, which they do by means of a spine-like weapon projecting from

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2 Cercaria Sacs:

1. A sac two lines long; c, oral cavity; b, alimentary canal; c, a cercaria developed within the sac; d, sporulæ not yet developed into cercariæ. 2. The sac of a different species remarkable for its abdominal processes. 3. Another species, more simple in form and structure.

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their head. The tail, as no longer needed, is now left behind, the closing of the wound through which the C. enters apparently nipping it off. Within the body which it enters, the C. loses all its spine, becomes encysted, and awaits its passive migration into an animal of higher kind, there to become a trematode worm. When it does not succeed in finding, in due time, a larva into which to enter, the C. gathers itself up into a ball; emits a mucous secretion, which soon hardens; and incessantly turning round within this mucous mass, becomes invested with a sort of shell, in' which form it is not unlikely to be swallowed by some vertebrate animal. The C. is not the immediate offspring of a parent like itself. It is generated in a curious little animated sac (see figure, taken from Von Siebold's work on Tape and Cystic Worms), which is to be found buried among the organs of fresh-water mollusks, and within which this development of young takes place by gemmation. See GENERATIONS,

TERNATION OF.

CEREA'LIA, or CE'REAL GRASSES, so named from Ceres (q. v.), are the plants which produce grain or corn; in other words, all the species of grass (Graminea) cultivated for the sake of their seed as an article of food. They are also called CORN-PLANTS or BREAD-PLANTS. They do not belong to any particular tribes of the great order of grasses, but differ from each other botanically, perhaps as much as any plants within the limits of that order. The seeds of the grasses in general being indeed farinaceous and wholesome, the employment of particular species as bread-plants seems to have been determined chiefly by the superior size of the seed, or by the facility of procuring it in sufficient quantity, and of freeing it from its unedible envelopes. Some of the grains, as wheat and barley, are produced in ears or closeset spikes; some, as a few of those called millet, in spike-like panicles; others, as oats and rice, in very loose panicles. The form and size of the grains vary not a little, some being roundish, and some elongated; maize is the largest; many of the millets are very small. The plants themselves vary in size almost as much as their seeds, the millets being the smallest, and maize the largest of ordinary corn-plants Buckwheat and Spurry are sometimes ranked with the C., but incorrectly, if the term is regarded as having any botanical limits, for they are not grasses; but their seeds are used in the same way. The Quinoa of South America, and the Kiery (AmaAL-ranthus) of India, with other plants of different orders, might be added to the list on the same account; even the Lotus of the Nile, the Victoria regia, and other species of water-lilies might thus be reckoned as cereal plants. The most extensively cultivated grains are Wheat (Triticum), Barley (Hordeum), Rye (Secale), Oats (Avena), Rice (Oryza), Maize or Indian Corn (Zea), different kinds of Millet (Setaria, Panicum, Paspalum, Pennisetum, and Penicillaria), and Durra or Guinea Corn (Sorghum or Andropogon). These have all been cultivated from time immemorial, and there is great uncertainty as to the number of species to which the many existing varieties belong; their original forms and native countries cannot confidently be determined. Barley, oats, and rye are the grains of the coldest regions, the cultivation of the two former extending even within the arctic circle. Wheat is next to these, and in the warmer regions of the temperate zone its cultivation is associated with that of maize and rice, which are extensively cultivated within the tropics. The millets belong to warm climates, and durra is tropical or sub-tropical. Rice is the food of a greater number of the human race than any other kind of grain.

CERCELÉE, or RECERCELÉE, in Heraldry, is a cross circling, or curling at the ends, like a

ram's horn.

CE'RCIS. See JUDAS' TREE. CERCOCE’BUS (Gr. tail-ape), a genus of monkeys, natives of Asia and Africa, included by some naturalists in the large genus Cercopithecus. These monkeys have large cheek-pouches, large callosities, and long tails. The species commonly called MANGABEYS, or WHITE EYELID MONKEYS, are commonly referred to this genus, besides the CALLITHRIX, or GREEN Monkey, and the MALBrouk, or Dog-TAILED BABOON.

CERDO'CYON (Gr. cunning-dog), a genus of Canide, apparently intermediate between true dogs and foxes, natives of South America. They are sometimes called Aguara Foxes. Their aspect is thoroughly vulpine, as are also their manners. Some of them add to the dispositions of ordinary foxes a singular propensity to steal and secrete brilliant or gaudy objects. A Brazilian species has been known to carry pocket-handkerchiefs into the woods. Some are natives of the coldest parts of South America, and have a rich fur.

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CERCOPITHE’CUS (Gr. tail-ape), a genus of morkeys, containing a large number of species, natives of Asia and Africa, but chiefly of Africa. They are called Guenons by French naturalists, but they have no common English name more distinctive than Monkey. They have cheek-pouches and callosities, and a long but not prehensile tail. A MONA, or VARIED MONKEY (C. Mona)-an African species

CERE. See BILL.

CERE'A, a town of Lombardy, about 19 miles south-south-east of Verona. It is a straggling place, with the remains of an old castle, and a population of 6000.

CEREBELLUM-CEREBRUM.

Maize has the greatest range of temperature.—| blindness. Disease or destruction of one corpus quad. Besides these, other grasses are cultivated to some produces blindness of the opposite eye. Probably their extent, in different parts of the world, for the grain connection with vision is not their only function. they yield a species of Eleusine (Mand) in India, and another (Tocusso) in Abyssinia; a species of Poa (Teff) in Abyssinia, and a species of Coix (Job's Tears) in India. Canary Grass (Phalaris) may also be named. Canadian Rice (Zizania) is used as a grain, but is scarcely cultivated, and the same remark applies to the Manna Grass (Glyceria) of the north of Europe, to some species of Bamboo (Bambusa), and to the Sea Lyme Grass (Elymus), which affords an esteemed article of food, in small quantity, to the inhabitants of Iceland.

Of all the C., wheat is by common consent admitted to be that of which the grain is best fitted for the making of bread, although others are to some extent employed for this purpose. But some, as rice and maize, are scarcely suited for it, and other methods are chiefly employed of preparing them for food. All the grains are also used to produce some kind of fermented liquor or beer, and spirituous liquors are obtained from them by distillation.

CEREBELLUM. See CEREBRUM.

CE REBRINE,

or CE'REBRIC ACID, is an organic acid of very complex composition, found in the liver, blood, and nerves, but especially the brain

of animals.

an

CE'REBRO-SPINAL FLUID. There is interval, termed the Sub-arachnoid Space, lying between the two innermost of the membranes of the brain and spinal cord-viz., the arachnoid and the pia mater. This space, which is narrow on the surface of the cerebral hemispheres, but is comparatively wide at the base of the brain between the two middle lobes of the cerebrum, and, posteriorly, between the hemispheres of the cerebellum and the medulla oblongata, is occupied by the C. F., which fills up the interval between the arachnoid and pia mater, and keeps the opposed surfaces of the former membrane (which is a close serous sac) in contact. The C. F. is a clear, limpid, slightly albuminous fluid, having a saltish taste, and a faintly alkaline reaction, and not containing more than 1.5 per cent. of solid matters. It varies in quantity from two to ten ounces, and is said to be most abundant in aged persons. Its chief use is to afford mechanical protection to the nervous centres, and to prevent the effects of external shocks or concussions.

CE REBRUM, CEREBE'LLUM. Cerebrum (Lat. the brain) is sometimes applied to the whole contents of the cranium or skull; but more usually it denotes the upper portion, while the under and posterior portion is called the CEREBELLUM, or little brain. In this article we shall briefly notice the chief results which have as yet been obtained regarding the uses of the various parts of the mass, referring to the article BRAIN for the necessary anatomical details.

The crura cerebri appear as the principal conductors of impressions to and from the cerebrum. When one is divided, the animal moves round and round, from the injured towards the sound side, as if from a partial paralysis of the latter side. The effect may be referred to the interruption of the voluntary impulses from the C., for although the cerebellum seems to have the office of combining the muscles, whose co-operation is necessary for each action, the effort of the will must proceed from the cerebrum.

The corpora quadrigemina are, as stated in the article BRAIN, analogues of the optic ganglia of the lower animals.' Their removal wholly destroys the power of seeing, and diseases by which they are seriously affected are usually accompanied with

The optic thalami probably participate slightly in the visual function of the corpora quadrigemina; but we have no definite evidence on this point. They are intimately connected with the power of movement. Destruction of one of them causes rotation of the animal, similarly to division of one of the crura cerebri. Longet has shewn, that after removing all the cerebral hemispheres and the corpora striata, the animal can still stand and walk, but that on removing one of the optic thalami, it falls down paralysed on the opposite side, or commences rotatory motion.

The function of the corpora striata is very uncertain; they have probably some connection with sensation and volition, the precise nature of which is at present unknown.

The parts hitherto considered-including the cerebellum-appear to comprise the apparatus (1.) For the direction and government of all the unfelt and involuntary movements of the parts which they supply; (2.) For the protection of sensations; and (3.) For the direction of such instinctive and habitual movements as do not require the exercise of any reasoning or intellectual act. They cannot be regarded as organs of the higher faculties of the

mind.

The functions of the cerebral hemispheres are, in the words of Dr. Kirkes (Handbook of Physiology), those of organs by which the mind, 1st, perceives those clear and more impressive sensations which it can retain and judge according to; 2d, performs those acts of will, each of which requires a deliberate, however quick, determination; 3d, retains impressions of sensible things, and reproduces them in subjective sensations and ideas; 4th, manifests itself in its higher and peculiarly human emotions and feelings, and in its faculties of judgment, understanding, memory, reflection, induction, and imagination, and others of the like class.

The evidences that the cerebral hemispheres are, in the sense and degree indicated above, the organs of the mind, are chiefly these: 1. That any severe injury of them, such as a general concussion, or sudden pressure by apoplexy, may instantly deprive a man of all power of manifesting externally any mental faculty; 2. That in the same general proportion as the higher mental faculties are developed in the vertebrate animals, and in man at different ages, the more is the size of the cerebral hemispheres developed in comparison with the rest of the cerebro-spinal system; 3. That no other part of the nervous system bears a corresponding proportion to the development of the mental faculties; 4. That congenital and other morbid defects of the cerebral hemispheres are, in general, accompanied with corresponding deficiency in the range or power of the intellectual faculties and the higher instincts.' See MIND, THE HUMAN.

Cerebellum.--The functions of this organ have been made the subject of much discussion and investigation. It is itself insensible to irritation, and has been cut away in various animals (by Longet and other French physiologists), without elicting signs of pain; moreover its removal or disorganisation by disease is generally unaccompanied with loss or disorder of sensibility, animals from whom it has been removed being apparently able to smell, see, hear, and feel, as perfectly as before. Flourens seems by his vivisections to have arrived at the correct view regarding the functions of this organ, and his results have been fully confirmed by Longet and others. and others. He extirpated the C. in birds by successive layers. Feebleness and want of harmony

CEREMONY-CERÉS.

of the movements resulted from the removal quoted), Carpenter's Human Physiology, Noble On of the superficial layers; when he reached the the Brain, Holland's Chapter on Mental Phiysiology, middle layers, the animals became restless; their and Brodie's Psychological Inquiries. movements were violent and irregular; but they were not convulsed, and their sight and hearing were perfect. By the time that the organ was entirely removed, the animals had completely lost the power of flying, walking, standing, and preserving their equilibrium. When a pigeon in this state was laid upon its back, it could not recover its former position; but fluttered its wings, and saw and tried

to avoid a threatened blow. Hence volition, sen

sacred rite). Almost any act, when performed in CE'REMONY (Fr. cérémonie; Lat cærimonia, a a regular, orderly, and formal manner, and when mode of its performance, becomes a C.; and the viewed, not with reference to its object, but the more entirely the attention of the performers - is withdrawn from the object of the act, and fixed upon the manner of its performance, the more ceremonious does it become. The purely formal character of C. is thus illustrated by Hooker: The name ceremony,' he says, we do not use in so large a meaning as to bring sacraments within the compass and reach thereof, although things belonging to the outward form and seemly administration of them are contained in that name. The remark is applicable to the most trivial ceremonies of social life and of state

sation, and memory were not lost, but merely the faculty of combining the actions of the muscles. From a large series of experiments of this kind, subsequently made on all classes of animals, Flourens infers that the C. belongs neither to the sensitive nor to the intellectual apparatus; and that it is not the source of voluntary movements, although it belongs to the motor apparatus; but that it is the organ for the co-ordination of the voluntary move-pageantry, as well as to the most sacred rites of ments, or for the excitement of the combined and religion, for a C. which is its own object, would scarcely be entitled to be regarded even as a ceremony. The most empty display has always the ulterior object of imposing on somebody.

harmonious action of the muscles.

This view is confirmed by the phenomena observed in certain cases of disease, and to a certain extent by comparative anatomy, for to each of the four classes of vetebrata-if we reckon amphibians and reptiles as a single class-the species whose natural movements require the most rapid and exact combinations of muscular actions are those in which the C. is most developed in proportion to the spinal cord; and if we compare different species of the same class, we usually find the development of the C. to correspond very closely with the perfection and variety of the muscular movements. For

example, in the frog the movements are exceedingly simple in character, consisting of little else than flexion and extension of the posterior limbs; and the C. of this animal is extremely small compared with the rest of the brain, being merely a thin narrow band of nervous matter. In the common sea-turtles, the movements of the body are of a more varied character, and the motions of the head and neck are more extensive; and here we have a much more highly developed cerebellum. In the alligator, again, a reptile whose motions closely resemble those of quadrupeds, the C. is still more fully developed.

The influence of each half of the C. is directed to the muscles of the opposite side of the body, and for the right ordering of the movements, the actions of its two halves must be mutually balanced and adjusted; for if the nervous structures uniting one of the halves of the C. with the medulla oblongata and spinal cord be divided, strangely disordered movements occur, the animal falling down on the side opposite to that which has been injured, and continually rotating round the long axis of its body, sometimes for several days, at the rate of fifty or sixty times in a minute. Similar movements have been observed in men in whom one of the crura of the C. has been diseased.

Ceremonies may be divided into four classes: 1. Religious ceremonies; 2. Social ceremonies; 3. State ceremonies; 4. International ceremonies.

Religious and state ceremonies will be treated of respectively under their various denominations; see, for the first, RITES, LITURGY, MASS, PROCESSIONS, &c.; and for the second, CORONATION, COURT, &c. Social C. will in a great measure fall under the PRESENTATION AT COURT, OPENING OF PARLIAMENT, &c. Social C. will in a great measure fall under the heads, ETIQUETTE, PRECEDENCE, COURTESY, FORMS OF ADDRESS, &c.; and international C. under DIPLOMACY, CONSUL, AMBASSADOR, &c.

CEREO'PSIS (Gr. wax-faced), a genus of birds of the family Anatide, to which the New Holland goose (C. Novæ Hollandia) belongs. This bird has been known since the southern shores of that country were first visited by navigators. There, and on the adjacent islands, it is found in great abundance; and the earlier navigators easily supplied themselves with fresh provisions by knocking them kown with sticks, so little were they acquainted with the danger to be apprehended from man. The cere is remarkably large, whence the name.

Phrenologists are of opinion, in accordance with the view originally propounded by Gall, that the C. is the seat of the sexual impulse and instincts; but this view has been long abandoned by almost all physiologists, for the reason that it has not been found to be sufficiently supported by anatomical and experimental facts, many of which are indeed directly opposed to it.

CE'RÉS, among the Greeks named Demeter, daughter of Chronos (Saturn), by Rhea (Ops), sister of Jupiter, Neptune, Juno, &c. She had the misfortune, along with her other brothers and sister, to be devoured by her father, who, however, vomited her forth again after taking the emetic which Metis gave him. By her brother Jupiter she became the mother of Persephone or Proserpina (q. v.). The chief myth relating to C. tells how her daughter Proserpina was stolen by Pluto, and how the mother wandered far in quest of the maiden. After travelling in human form nine days, and everywhere distributing her gifts to mankind, she excited the pity of Jupiter, by whom Mercury was despatched to bring back Proserpina from the infernal world, but on the condition that she must spend there a third part (or, as others say, one-half) of every year. The myth of C. was symbolical of the growth of grain; some consider that this is intimated in the name Demeter, which is thought to be equivalent to ge meter, 'Mother Earth. The Our limited space compels us to leave altogether relations of the worship of C. with agriculture, untouched many most interesting topics in Cerebral social order, &c., were expressed in her two great Physiology, as, for instance, the duality of the festivals-the Eleusinia (q. v.) and Thesmophoria brain, the plurality of the cerebral organs, &c. The (q. v.). C. was especially worshipped in Crete, reader who wishes for further information, is referred Delos, Sicily, Asia Minor, Arcadia, Argolis, and to Kirkes's Physiology (from which we have freely Attica. Bulls, cows, pigs, honey-cakes, and fruits

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