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PART III. ANIMALIA ARTICULATA.
Body surrounded by jointed rings which answer tite * of a bony skeleton. Brain is placed upon the cesophagus, and furnishes, those parts with nerves which adhere to the head. The two chords which embrace the oesophagus are continued along the belly, and unite from time to time into double knots or ganglia, whence the nerves are sent to different parts of the body. . Each ganglion seems to perform the function of the brain for the surrounding parts.
Body soft, more or less elongated, divided into a very considerable number of segments.
Gen. 1. Serpula.
Gen. 2. Sabella.
Gen. 3. Terebclla.
Gen. 4. Amphitrite, &c.
ORDER II.-BRANchii super DoRSo.
Their organs, and particularly their branchiae, are distributed nearly equally along the body, or at least in the medial line.
Group Nereides, including two or three genera.
Gen, 1. i.
Gen. 2. Aphrodita.
Gen. 3. Amphinoma.
Gen. 4. Arenicola.
ORDER III.—SINE BRANchiis.
Without any apparent organ of respiration, and they appear to respire by the surface of the skin.
Family 1. SETIs INSPEUcTA.
Gen. 1. Hirundo.
The situation and form of their branchiae, the manner in which the head is pointed to the trunk, and the organs of mastication, will furnish foundations upon which we may erect the following orders:—
Bear a feeler upon each mandible; have the eyes moveable and the head confounded with the trunk; the branchiae pyramidal; the leaflets or plumose laciniae seated at the outer base of the nippers, and the feet properly so called, and are concealed under the edges of the shell: of the first family of this order the genus cancer may stand as a sample.
Bear also a feeler upon each mandible: have the eyes also moveable; but the head is distinct from the trunk, and is divided into two parts, of which the outer bears the antennae and the eyes; the branchiae, in form of pannicles or bundles, are suspended under the tail, which is very large, behind each pair of finned feet with which it is furnished underneath.
Bear also a feeler upon each mandible; but their eyes are immoveable; the head is distinct from the trunk and of one piece; the branchiae are vesicular, and are seated at the inner base of the feet, with the exception of the first pair.
Mandibles without feelers, and the mouth always composed of several maxillae, of which the lower imitate a lip with two feelers. The branchiae are commonly seated under the abdomen; all the feet are proper for locomotion or pretension. Onisci. ORDER. V.-BRANchiopoda. Mandibles without feelers; the mouth is sometimes in the form of a beak, sometimes of soveral maxillae; but the two lower ones have the appearance of a lip with two palpi; feet in form of fins; the branchiae are attached to a part between them; the body is generally covered with a shell with which the head is confounded. Monoculi. CLAss III.-ARACHNIDA. Head destitute of antennae; the external orifices placed under the belly, or the posterior extremity of the breast, lead in some genera to sacs which occupy the place of lungs; in other genera there exist true tracheae, which are distributed to every part of the body. ORDER. I.-PULMonARIA. Furnished with pulmonary sacs, and six or eight eyes; they have a pair of mandibles, two maxillae, two feelers, and one lip. Family 1. ARANEE. Family 2. PEDIPALPA. Paipi like advanced arms. Tarentulae. Scorpiones. ORDER II.-TRACHEATA. Organ of respiration ranged and ramified; eyes from two to four. Family 1. Scorpiones FALS1. Solpuga. Chelifer. Family 2. PycnogoNIDA. Trunk composed of four segments; truncated at each extremity by a tubular joint. Pycnogonum, &c. Family 3. PHALANGITA, PHALANGIUM, TIRo, AcAREUs, &c. &c.
CLASS IV.-INSECTA. ORDER. I.-MYRIApoda. Julus. ORDER II.--THYsANURA. Lepismae. ORDER III.-PARASITA. Pediculus. ORDER IV.-Suctor.I.A. Pulex. ORDER V.-ColeopterA. ORDER VI.-ORTHopTERA. ORDER VII.-HEMIPTERA. ORDER VIII.-NEUROPTERA. ORDER IX.-HYMENoPTERA. ORDER X.-LEPIDoPTERA: ORDER XI.-RHIPIPTERA. ORDER XII.-DIPTERA. As the subjects pertaining to this class have been treated at considerable length, in the article ENToMology, the ingenuity of the reader it is trusted by drawing supplies of matter thence will compensate our brevity, and will spare us a particular discussion of the elements which compose this subdivision of the animal kingdom.
Medusa of Linné.
In conformity to our promise of regarding the complexity of form as it graduated downwards, we might stop here, since the eudora present nothing to our sight but the similitude of a crown with a
cross upon it, without any aperture for the intermission of nutriment; but it will be expedient after the example of Cuvier to add the two following classes, which will render the enumeration complete:— CLAss IV.—POLYPI. 'ORDER. I.-PolypI NUDI.
We have thus given a cursory outline of the leading divisions and sub-divisions of the animal king. dom, unfolded the general principles of classification, and would gladly have dealt out our illustration with a more liberal hand had not our limits withheld us; but it is hoped that the student of this department of science will, from a perusal of this article, derive some important hints towards the method of integrating the gleanings of his daily experience, and of acquiring the habit of generalising from the principles or facts of natural history which jointly constitute the logic of zoology.
ZOONIC Acid. “Berthollet,' says Dr. Thomson, “has obtained a peculiar acid by distilling animal and vegetable substances, to which he has given the name of zoonic acid.—Ann. de Chim. xxvi. 86. He procured it by distilling the gluten of wheat, the yeast of beer, bones, and woollen rags; and concludes, therefore, that it may be produced by the distillation of all animal substances. To obtain this acid pure, he mixed lime with the distilled liquid, after having separated the oil, which it always contains (for the product of the distillation of animal substances is chiefly oil and carbonate of ammonia). He boiled this mixture till the carbonate of ammonia was exhaled: he then filtered it, added a little more lime, and boiled it again till the smell had gone off entirely. The liquor, which now contained only zoonite of lime, he filtered again, and then added a little water, impregnated with carbonic acid, in order to precipitate any lime which might happen to be dissolved in the liquid without being combined with the zoonic acid. After concentrating the zoonate of lime, he mixed it with phosphoric acid, and distilled it in a retort. At a heat nearly equal to that of boiling water, the zoonic acid passes over in a state of purity. The zoonic acid has an odor like that of meat when frying, and it is actually formed during that process. It has an austere taste. It gives a red color to paper tinged with turnsol. With alkalies and earths it produces salts which do not appear capable of crystallising. It forms a white precipitate in the solutions of acetite of lead and nitrate of mercury. Part of the
zoonic acid seems to be destroyed by the action of heat during the distillation of the zoonate of lime with phosphoric acid; for the liquor, which is in ebullition, becomes brown, and grows black at the end of the operation. Hence Berthollet concludes that the zoonic acid becomes carbon. The zoonate of silver, when kept, becomes gradually brown: hence he concludes that the acid contains hydrogen. Nothing more is at present known concerning this acid. Trommsdorf supposes it the same with the sebacic acid; but this has not been proved, nor even rendered probable.”—Syst. of Chem. vol. ii. p. 162, 163. Thenard indeed has demonstrated that this supposed new acid of Berthollet's is only a combination of acetic acid with animal matter. ZOONOMIA (from owov, an animal, and vouco, a law; q. d. the laws of animated nature), the title of an ingenious and admired work of learning and fancy, by Dr. Darwin. ZOOPHYTE, in natural history. See Zoology. ZOOTOMY, of Zoov, animal, and rspyw, I cut, the art or act of dissecting animals, or living crea: tures. It is therefore the same with anatomy, or rather comparative anatomy. See ANATomy. ZOPARITUS, in ancient geography, a town of Asia, in Melitene, on this side of the Euphrates.— Ptolemy. ZOPH, a town of Syria, twenty-five miles S.S.E. of Jerusalem; also a district on the north part of the government of Diarbekir. ZOPHAR, the Naamathite, one of Job's three uncharitable friends. See Elihu, and Job.