THE MUSCLES OF THE NECK AND BACK 181 



tubercles of the transverse processes of the five cervical vertebrae, 

 second to sixth inclusive. 



M. longissimus capitis (trachelomastoid), by four tendons 

 from the upper dorsal transverse process, and from the articular 

 process of the lower three or four cervical vertebrae, into the 

 posterior margin of the mastoid process under the splenius 

 capitis and sternomastoid. It shows a tendinous intersection 

 near its insertion; it is the only muscle between the splenius 

 and complexus. 



Musculi spinales, spinous muscles, have an arched direction. 

 1. M. spinalis dorsi, close inside the longissimus dorsi and 

 connected with it; origin, lowest two or three dorsal spines 

 and from tendons passing from the upper lumbar spines to 

 the longissimus dorsi; inserted by four to nine slips into the 

 upper dorsal spines. 



2. M. spinalis cervicis, inconstant or different on the two 

 sides from the ligamentum nuchae and seventh cervical 

 spine, and one or two above or below this; inserted into 

 the spine of the axis or also into the third and fourth cervi- 

 cal spines. 



Complexus Muscle. Origin, from the tips of the transverse 

 processes of the upper six or seven thoracic and the last cervical 

 vertebrae, and from the articular processes of the fifth, sixth, 

 and seventh cervical vertebrae; forming a broad muscle, which 

 is inserted into the innermost depression between the two 

 curved lines of the occipital bone. 



Fifth Layer. (a) Mm. Semispinalis (half -spinous). (1) M. 

 semispinalis dorsi, by five or six tendons from the trans- 

 verse process of the dorsal vertebra, from the sixth to the 

 tenth inclusive; inserted by just as many tendons into the 

 spines of the upper four dorsal and Blower two cervical vertebrae. 

 (2) M. semispinalis cervicis, covered by the complexus, rises 

 nearly from the insertion vertebrae of the preceding, viz., 

 upper five or six dorsal transverse processes; inserted into the 

 cervical spines from the second to the fifth, inclusive, being 

 thickest into the axis. (3) M. semispinalis capitis (complexus) 

 rises by two sets of heads; the inner, or biventer cervicis, rises 

 from three or four dorsal transverse processes between the 

 second and sixth; its superficial fibers are inserted into the 

 external occipital protuberance beside the ligamentum nuchae; 

 its deeper fibers join the external head. The outer head rises 



