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 2!^ Part II. ANA r O M Y. being often mixed with the fhort fafciculi of the fpinalis fomething like the facro-lumbaris, but more flefhy and major. The reft lie diredtly between the extremities of thicker, fituated between the fpinal apophyfes and the mufcle jud mentioned, from which it is divided by a two neighbouring fpinal apophyfes, being feparated from fmall, fatty, or cellular line ; but at the lower part they their fellows on the other fide by the fpinal ligament. are confounded together. It covers the femi-fpinalis, or They are fmaller and thinner than thofe of the neck, tranfverfo-fpinalis dorfi, and the femi-fpinalis lumborum. and are properly enough termed inter-fpinales. Its' upper part lies between the facro-lumbaris and tranfverfalis colli. DORSI MINORES. Its inferior infertions are partly by diftindt tendinous TRANSVERSALES particular mufcles of this kind are found fixed portions, and by a broad aponeurofis common to it with to Some the facro-lumbaris; and partly by a large fafciculi of the extremities of the three lowed: tranfverfe apophyflelhy fibres, which, at firit fight, feem to compofe one fes of the back. The reft are all in fome meafure contiuniform mafs. It is fixed, by the long, flat, tendinous nuations of the tranfverfalis major. portions of different breadths, to the lafl fpinal apophyfis of the back, to all thofe of the loins, and to one or two Semi-SpinalIs five Transverso-Spinalis Dorsi. of the fuperior fpines of the os factum. Thefe portions This is a flefhy mafs, which, from all the fpinal and lie at different diftances from each other, but are all con- tranfverfe apophyfes of the back and loins, is extended nedted by a thin aponeurofis fixed to their edges. fafcfculi over the vertebra themfelves. From thence they run up. obliquely, diverging from intoIt diftindt is made up, like that of the neck, of feveral oblique the apophyfes ; and, beginning to be flefhy at their inner converging mufcles, the uppermoft of 'which is or anterior fides, they terminate above in fmall roundifh fixed belowvertebral to the third tranfverfe apophyfis of the tendons, inferted in the extremities of the feven upper back, and above fpinal apophyfis. The tranfverfe apophyfes of the back, and in the neighbour- loweft is fixed belowto tothethefirft third tranfveife apophyfis of ing-ligaments of all the true ribs. loins, and above to the laft fpinal apophyfis of the The other inferior infertion wholly fiefiiy, is partly in the the inner or forefide of the aponeurofis of the facro-lum- back. They may be divided into external, which are firft baris, and partly in the upper portion of the os facrum, difcovered;. and internal, which lie immediately on the: being from thence continued to the great tuberofity of vertebra. The external, from the firft vertebra to the the os illium. inclufively, appear to be longer than the inter-, From thence this uniform m&fs of flefhy fibres runs up feventh, in a courfe almofl diredt, croffing the tendinous portions nal, which are covered by them. which are more oblique ; and join the inferior fibres of the facro-lumbaris by large fafciculi inferted in the tranfSpinalis Lumborum, verfe and oblique apophyfes of the vertebra of the loins. TransversoSacer Veteribus. The fibres of this portion go afterwards to the ribs, being inferted by planes more or lefs fiefiiy, in the lower This mufcle is compofed of feveral oblique converging convex edge of all the falfe ribs, between the condyles of'tranlverfo-fpinal mufcles, in the fame manner as in or tuberofities and the angles. the back and neck; and if lies between the fpinal and At the fixth or feventh vertebra of the back, one or oblique apophyfes of tire loins, reaching to the os fatriore of the tendinous portions often communicate with crum. fome fafciculi of the femi-fpinalis,. or tranfverfo-fpinalis The loweft of thefe mufcles are fixed to die fnperior > dorfi. lateral parts of the os facrum, to the ligamentum facroiliacum, and to the pofterior fuperipr fpine of the Os ilium. The reft are fixed to the three loweft tranfverfe SPINALIS DORSI MAJOR. apophyfes, and to the four loweft oblique apophyfes of This is a pretty long and^ flender mufcle, lying up- the loins, and to their lateral tuberofities. From thence on the lateral part of the extremities of the fpinal apo- they fun up to all the fpinal apophyfes of thele vei tebra, : phyfis of the back. the external, or rhofe that appear firft, being longer than ' It is compofed of feveral mufcular fafciculi of diffe- the internal, which lie immediately on the vertebra, erent lengths, which, croffing each other, are inferted la- fpecially toward the lower part. terally by fmall tendons in the fpinal apophyfes from the fecond, third, or fourth vertebra of the back; and fometimes, though feldom, from the laid of the neck, or Spinales & Transversales Lumborum.', firft of the back, all the way to the firfl or fecond verte- There are fome fafciculi which run up from the fnbra of the loins, with feveral irregular decufiations, which perior falfe fpines of the os facrum, to the lower fpinal vary in different fubjedts. apophyfes of the loins, which may be looked upon as fo many fpinales lumborum majores. There are likewife fpinales minores between the fpinal apophyfes of SPINALES DORSI M INGRES. fome the and tranfverfales miriores between the tranfThese mufcles are of two kinds. Some go laterally verfeloins, apophyfes, from the extremity of cne fpinal apophyfis to another; breadth. - ' which are fometimes of a confiderable ‘ Quadratus