Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/536

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roots of the plants, and in a condition to be gathered for ufe. The analogy of the life of other animals of this kind, gives us, however, no room to doubt but that they, foon after their corn- ing from the egg, fix themfelves to fome plant, and there grow and continue to receive their nourifhment ; but how after this they acquire the fhape of a ball lodged in a cup, requires a nice future obfervation. lb. p. 117. COCCYG^US anterior, a mufcle fixed, by a broad infertion, in the anterior portion of the fmall tranfverfe ligament at the upper part of the foramen ovale of the os innominatum ; from thence it runs between this great ligament and themufculus obturator intimus, with which it is often confounded by ana- tomifts, and contracting in breadth, it is inferted in the lower part of the os coccygis. Win/low's Anatomy, p. 250. Coccyg/eUS poferior, a mufcle fixed to the inner, or concave edge of the two firft vertebras of the os facrum, to the inner and lower eds;e of the ligamentum facro-fciaticum, and to the fpineoftheosifchium ; from thence, contracting in breadth, it is inferted in the infidc oftheos coccygis, above the anterior. IVinjtozvs Anatomy, p. 250. COCCYGIS as (Cycl.) — This is in fome mcafure an appendix to the os facrum ; its figure is in fome degree like that of an - -inverted pyramid a little bent forward toward the pelvis. The anterior fide is flat, the pofterior a little convex; the four cr five pieces it is made up of are fomething likefalfe vertebra ; they are ufually joined by cartilages more or lefs pliable, and fometimes all the pieces are entirely cemented together. The jfirft piece is the largcft, and on each fide of its bans there are fometimes fmall apophyfes, or cornua, which are clofely joined to the extremity of the os facrum. It has alfo fometimes a kind of tranfverfe apophyfes with fmall notches on their upper • part, which joining with thofe of the laft piece oftheos facrum, form a pair of holes fituated in the fame row with the other large ones. The other pieces of the os coccygis are a kind of irregular fquares, diminifhing in fize as they defcend, fo that the laft is like a fefamoide bone. WivfovJs Anatomy, p. 61. ■ The os coccygis may be thruft inwards by a violent fall or blow, and it is often puthed outward in hard births. When this hap- pens it is ufually attended with violent pain and inflammation about the lower part of the fp'ine; abfeeffes form intheintefti- num rectum, and the ficces are conftipated, or fupprefled. The replacing this bone is not very difficult, if an able furgcon is applied to in time. If it be thruft outwards, it muft be de- prefl'ed into its right place by the thumb ; after which com- prefles dipt in warm wine, or fpirit of wine, are to be applied to the part; thefe are to be made broad above, and narrow be- low, that they may fill up the pofterior finus of the nates ; and thefe may be conveniently held on by the T bandage. When the os coccyx happens to be luxated inwards, the fore- finger is to have its nail cut clofe, and being dipt in oil, is to be introduced up the anus, and muft be thruft in as far as pof- fible, that it may the more readily drive out the deprefled bone: the other fingers being placed externally, are to con- duct; the bone into its right pofture. When the bone is re- placed, the patient muft reft fome time upon a bed, and when he fits up, it muft be in a chair with a hole in its bottom, left the affected part fhould otherwife be comprefled or difturbed. Heifer, Surg. p. 157- Coccygis ofis mufuli. Thefe are fmall, thin, radiated mufcies, lying on the inner, or concave fide of the os facrum, and neighbouring parts of the pelvis. They are four in number, two on each tide, one placed more forward, the other more backward ; for which reafon the firft muft be termed coccygarzts anterior, five Ijchio-toccyg^us, and the other coccygaus poferior, five fa< ro-coccyga-us. I'f'info-w's Anatomy, p. 249. COCCYX, in 'ichthyology, a name given by Ariftotle and the other old Greek writers to the fiih called cuculus and lyra by other authors. It is a fpecies of the trigla, diftinguifhed by Artedi by the name of trigla all over red, with a bifid fnout, and the coverings of the gills ftriated. Sec the articles Cuculus, and Tricla. COCETUM, among the ant'ients, a kind of drink made of ho- ney and poppies. Pitife. Lex. Ant. in voc. COCHINEAL (Cycl.) — Befidestbeufes of cochhieal enumerated in the Cyclopedia, it has many medicinal virtues afcribed to it, beinw efteemed a great cordial, fudorific, alexipharmic, and febrifuge. For the hiftory of cochineal, fee the article Pro- gall ir.fcl. COCHLEA, (Cycl ) the name of a very large family of fea lhell-fiih, which are divided by authors into three diftinct ge- nera from the figure of their mouti s, lomc of which are cir- cular, fome femicircular, and fome oval. Thefe are expreffed by the generical names, tochlea: lunares, eschlea feinilunai es, and cochlea ore deprejjb. The two former genera fee under the ar- ticles Lunaris cochlea, and Semilunaris cochlea. The characters of the third are thefe ; it is an univalve fhcll of a broaa figure with a conoide bafe, and an elevated fi>m- mit, or fometimes a plane and dcpr^Trd one. It is umbili-
 * cated, and of a pearly colour within, and has a mouth of an

oval figure, fometimes furniihed with teeth, fometimes with- out any. The conic figure of thefe (bells ufually diftinguifh.es them at firft fight from all the other kinds. Some of the fpecies of this genus have their apex elevated to a confiderablc height, and forming feveral fpiral turns. Thefe arc 4

properly Cuiijd fqh&ti by the French, and trochi bv the suthorq of other nations. Otheri have the apex lefs elevated, and are more of the common lhape of fnails. And finally, fome of them have the apex quite dcpreiTud. This is enough to fbew that in fhclh, in general, the elevation of the apex is no genu- ine character of a genus. Among the trcchi there istineimgle fpecies which is umbilicated, the others are none of them fo j and hence this forms a very grand diftinetion Uondchtius obferves that this genus of cochlea was called trochus from the refcmblancc of fome of the fpecies to the lhape of a boy's top, which he whips about. Rondelct. de Aquat. Mdtcv.md. de Teftnc.

The fpecies of the t?-och"s are thefe : 1 . Of the exerted-head- ed, there arc thefe. r. The variegated or marbled frocbus. 2. The punctuated trochus. 3. The green trochus. The fecond auJ third fpecies aflume very different appearances when they have palled through the hands of the poliflicr, and are preferved in the cabinets of collectors in fuch a ftate as to be with diffi- culty known; the marbled trochus appearing elegantly fmooth, and fpotted with red and white, and the other, or green tro- chus, lofing all its diftinguifhiiiL; colour, and appearing wholly like mother of pearl. Befide thefe, there arc fome fpecies re- markable for their tuberofities, and thence called knotted tro- ch't. Of thefe there are, 1. The green kind. 2. The red, knotty trochus. 3. The grey, knotted trochus. And, 4. The yellow one.

Of thofe trochi which have the apex lefs exerted, and have a larger and rounder mouth, and are umbilicated, we have the following fpecies. 1. 'I he widow trochus. z. The magpye t trochus. 3. The tiger trochus. 4. Thefharp-headedf/^owj, with exerted ribs. 5. The trochus furniihed with tubera, and prickles. 6. The lamp, or pagod trochus. J. The white tro- chus, with high ribs. 8. The trochus, with a regular feries of fpines. Q. The rough trochus, with an operculum. 10. The rough button t7'ochus. with teeth in the mouth. 1 1, The fpur trochus, with fpines difpofcd in a regular circle. 12. The lefs aculcated fpur trochus. 1 ?. The golden trochus, with a filver umbo ; this, when robb'd of its outer coat, by polifh- ing, appears all over filvery. Thefe are the known (pedes of trochi with exerted apices.

Of the tro.hi with deprefled apices we have only the following known fpecies. 1. The antique lamp trochus, with a wide and flat mouth 2. The red and white lin'd trochus. 3. The trochus, with a dentated mouth. 4. The trochus called St.Hu- bert's horn, with a folded lip. 5. The hollow-headed trochus, with yellow ftreaks. 6. The all yellow, hollo w-heatied, tro- chu<. 7. The fiat-mouthed ladder trochu<. 8. The brown trochus, veined with white and yellow. And, 9. The whitifh trochus. with yellow lines and fpots.

From the figures of thefe feveral fpecies of fhells, it will be ea- fily feen that the name trochus, according to the common de- rivation of the word, very badly cxprefTes the feveral kinds, fome of which are of that figure, and fome no way approach- ing to it. They are much better expreffed by the n.mie cochlea ore deprejjh, which conveys an idea of an ablblutc diftinetion, which takes place in them all, and in no other fhells. flee Tab. of Shells, N° 5, b, 7. Hift. Nat. Eclair, p. 260. Cochlea of the ear* The parts to be diftinguifhed in this in its true filiation, are the bafis, the apex, the fpiral lamina, the half feptum, by which its cavity is divided into two half ca- nals ; the fpindle round which the- ochea turns ; and laftly, the orifices and union of the two ducts. The bafis is turned di- rectly inward, toward the internal foramen auditorium; the apex outward; and the axis of the fpindle is nearly horizontal ; but in all of thefe allowance muft be made for the obliquity of the os pctrofum, in which they lie. The bafis of the cochlea is gently hollowed, and towards the midJk is perforated by fe- veral fmall holes. 1 he fpindle is a kind of fhort cone, with a very large bafis, which is the middle of the bafis of the cochlea ; through its whole length runs a double fpiral groove, which, through a microfcope, {hews a great number of pores. *The coch'ca makes about two turns and a half from the bafis to the apex, and the two ducts being flrictly united together, through their whole courfe, form an entire common feptum, which muft not be confounded with the half feptum, or fpiral lami- na, as is often done. The firft of thefe may be properly termed the common feptum, the other the particular, or half feptum; both of them are clofely joined to the fpindle, being thicker there than in any other place. The common feptum is complcat, and feparatcs the turns entirely from one another, whereas the half feptum in the fkelcton is only a fpiral lamina, the breadth of which is terminated all round by a very thin border lying tn the middle cavity of the coc' lea. In a natural ftate there is a membraneous half feptum, which completes the partition l-etween the two duds. The two half canals turn jointly about the fpindle, one being fituated toward the bafis of the cochlea, the other toward the apex ; for which reafon, one of them may very well be termed the internal, the other the external ; the ufual diviiion of them into the upper and lower flight, not being agreeable to the natural ftate, but liable to convey a falfe idea of it. The fpiral voiute of the colchea be- gins at the lower part of the veftibulum, runs from thence fur- ward to the top, then backward down to the bottom, after- wards upward and forward, and fo on from the bafis, which is

turned