Page:Encyclopædia Britannica, first edition - Volume I, A-B.pdf/258

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XXX (216) XXX

ANATOMY. it6 Part II. of the ear, and lower part of the throat. It is in a ing along all the fide of the neck, up to the ear, where manner compofed of two mufcles, united at the upper part it increafes a little in breadth. through their whole breadth, andfeparated at the lower. It is fixed, by one extremity, in all the tranfverfe aIt has two infertions below, both of them flat, and a pophyfes of the neck, except the firft, by the fame numlittle tendinous. The firft is in the upper edge of the ber of digitations or branches, moftly flefliy, and difpofed fternum, near the articulation of the clavicula; the o- obliquely. ther in the clavicula, at a fmall difb.nce from the fternum. From thence it afcends, and having reached above the The fternal portion pafies foremoft, and covers the tranfverfe apophyfis of the firft vertebra, it forms a fmall clavicular, both forming one body or belly, which run- broad plane, by which it is inferted in the pofterior part ning in the fame oblique diredtion to the apophyfis ma- of the apophyfis maftoidaeus. ftoidseus, is inferted in the upper and back-part of that procefs ; over which it likewife fends off a very broad RECTUS MAJOR. aponeurofis, which covers the fplenius, and is inferted in This is a fmall, flat, fhort mufcle, broad at the upthe os occipitis. per part, and narrow at the lower, fituated obliquely bethe occiput and fecond vertebra of the neck. SPLENIUS fivS MASTOIDvEUS POSTERIOR. tween It is fixed below to one branch of the bifurcated fpine This is a flat, broad, oblongmufcle, fituated oblique- of the fecond vertebra of the neck, at a tuberofity which ly, between the back-part of the ear, and the pofterior is often found at the upper part of that branch. From and lower part of the neck. It is partly fingle, aO<J thence it afcends a little obliquely outward, and is infertpartly made up of .two portions, one fuperior, the other ed in the pofterior part of the inferior tranfverfe line of inferior. the os occipitis, at a fmall diftance from the crifta, being The fuperior portion is fixed to the extremities of the a little covered by the obliquus fuperior. three or four loweft fpinal apophyfes of the neck, ind of the firft, or firft and fecond, of the back. RECTUS MINOR. It is likewife fixed to the edge of the inter-fpinal liTh is mufcle is like the former, and it has alfo a fmall gaments of the other vertebra. From thence it runs up obliquely toward the maftoid infertion below, in the pofterior eminence of the firft verapophyfis, partly under the upper extremity of the fter- tebra. From thence it afcends laterally, and is inferted no-mailoidaeus, and is inferted in the upper part of that immediately under the pofterior part of the inferior tranfprocefs, and along the neighbouring curve portion of the verfe line of the os occipitis, in a fuperficial foflula on •:one fide of the crifta occipitalis. tranfverfe ridge of the os occipitis. The inferior portion of the fplenius is fixed to three or four fpinal apophyfes of the back, beginning by the OBLIQUUS SUPERIOR five MINOR. fecond or third. From thence it runs up, being clofely united to the other portion, till it reaches the fuperior This mufcle is fituated laterally between the occiput and lateral part of the neck, where it feparates from it, and firft vertebra, being nearly of the fame figure with two refti. It is fixed to the end of the tranfverfe and is inferted in the tranfverfe apephyfes of the three or the apophyfis of the firft vertebra; from whence it runs upfour fuperior vertebra of the neck, by the fame number ward and very.obliquely backward, and is inferted in the of extremities, a little tendinous, which, however, are tranfverfe line of the os occipitis, altnoft at an equal difometimes only two in number. ftance from the crifta and maftoid apophyfis, between the reeftus major and compleftus minor. COMPLEXUS. This is a pretty long and broad mufcle, lying on the OBLIQUUS INFERIOR five MAJOR. pofterior lateral part of the neck, all the way to the occiput. It is complicated, by reafon of the decuffations It is fituated in a contrary direftion to the obliquus fuof its different portions ; from which it has its name. perior, between the firft: and fecond vertebra of the neck, It is fixed below, by fmall fhort tendons, to the tranf- refembling that mufcle in every thing but the fize. It is verfe apophyfes of all the vertebra of the neck, except fixed below to one ramus of the bifurcated fpinal apophyfis the firft, to which it is fixed only near the root of its of the fecond vertebra, near the infertion of the re<Sus tranfverfe apophyfis. From thence it runs up obliquely major; from Whence it runs obliquely upwards and outbackward, croffing under the fplenius, and often commu- ward, and is inferted in the end of the tranfverfe apophyfis of the fiift vertebra, under the lower infertion of nicating with it, by fome fafciculi of fibres. It is afterwards inferted above, bya broad fiefhy plane, the obliquus fuperior. in the pofterior part of the fuperior tranfverfe line of the os occipitis, near the crifta orfpine of that bone. RECTUS ANTICUS LONGUS. This mufcle is, in fome meafure, of a pyramidal fiComplexus Minor five Mastoidjeus Lateralis. gure, lying along the anterior and lateral parts of the verThis is a long, {lender, narrow indented mufcle, ly- tebra of the neck, all the way up the balis cranii. ^