MYOLOGY 



dorsi, and is intimately blended with it ; it arises by three or four tendons from the 

 spinous processes of the first two lumbar and the last two thoracic vertebrse : these, 

 uniting, form a small muscle which is inserted by separate tendons into the spinous 

 processes of the upper thoracic vertebrse, the number varying from four to eight. 

 It is intimately united with the Semispinalis dorsi, situated beneath it. 



The Spinalis cervicis (Spinalis colli) is an inconstant muscle, which arises from 

 the lower part of the ligamentum nuchse, the spinous process of the seventh cer- 

 vical, and sometimes from the spinous processes of the first and second thoracic 

 vertebras, and is inserted into the spinous process of the axis, and occasionally into 

 the spinous processes of the two vertebrae below it. 



The Spinalis capitis (Biventer cervicis) is usually inseparably connected with the 

 Semispinalis capitis (see below) . 



The Semispinalis dorsi consists of thin, narrow, fleshy fasciculi, interposed 

 between tendons of considerable length. It arises by a series of small tendons 

 from the transverse processes of the sixth to the tenth thoracic vertebrse, and is 

 inserted, by tendons, into the spinous processes of the upper four thoracic and lower 

 two cervical vertebrse. 



The Semispinalis cervicis (Semispinalis colli), thicker than the preceding, 

 arises by a series of tendinous and fleshy fibers from the transverse processes of 

 the upper five or six thoracic vertebrse, and is inserted into the cervical spinous 

 processes, from the axis to the fifth inclusive. The fasciculus connected with the 

 axis is the largest, and is chiefly muscular in structure. 



The Semispinalis capitis (Complexus) is situated at the upper and back part 

 of the neck, beneath the Splenius, and medial to the Longissimus cervicis and 

 capitis. It arises by a series of tendons from the tips of the transverse processes 

 of the upper six or seven thoracic and the seventh cervical vertebrse, and from the 

 articular processes of the three cervical above this. The tendons, uniting, form 

 a broad muscle, which passes upward, and is inserted between the superior and 

 inferior nuchal lines of the occipital bone. The medial part, usually more or less 

 distinct from the remainder of the muscle, is frequently termed the Spinalis capitis; 

 it is also named the Biventer cervicis since it is traversed by an imperfect tendinous 

 inscription. 



The Multifidus (Multifidus spince) consists of a number of fleshy and tendinous 

 fasciculi, which fill up the groove on either side of the spinous processes of the ver- 

 tebrse, from the sacrum to the axis. In the sacral region, these fasciculi arise from 

 the back of the sacrum, as low as the fourth sacral foramen, from the aponeu- 

 rosis of origin of the Sacrospinalis, from the medial surface of the posterior superior 

 iliac spine, and from the posterior sacroiliac ligaments; in the lumbar region, 

 from all the mamillary processes; in the thoracic region, from all the transverse 

 processes; and in the cervical region, from the articular processes of the lower 

 four vertebrse. Each fasciculus, passing obliquely upward and medialward, is 

 inserted into the whole length of the spinous process of one of the vertebrae above. 

 These fasciculi vary in length: the most superficial, the longest, pass from one 

 vertebra to the third or fourth above; those next in order run from one vertebra 

 to the second or third above; while the deepest connect two contiguous vertebrse. 



The Rotatores (Rotatores spince) lie beneath the Multifidus and are found only 

 in the thoracic region; they are eleven in number on either side. Each muscle is 

 small and somewhat quadrilateral in form; it arises from the upper and back part of 

 the transverse process, and is inserted into the lower border and lateral surface of 

 the lamina of the vertebra above, the fibers extending as far as the root of the spinous 

 process. , The first is found between the first and second thoracic vertebrse; the 

 last, between the eleventh and twelfth. Sometimes the number of these muscles 

 is diminished by the absence of one or more from the upper or lower end. 



The Interspinales are short muscular fasciculi, placed in pairs between the 



