POSTERIOR SERRATI MUSCLES. 



233 



passing in a nearly vertical direction ; and those of the fifth group, confined 

 to the upper part of the vertebral column and to the head, may be looked 

 upon as combining some examples of the others. 



SERRATI MUSCLES. The serratus posticus superior is a thin flat muscle, 

 which arises from the lower part of the ligamentum nuchse and from the 

 spines of the last cervical and two or three upper dorsal vertebrae by a flat 

 tendon inclining downwards and outwards, and forming about a third of the 

 length of the muscle ; it is inserted by four fleshy digitations into the 

 second, third, fourth, and fifth ribs, a little beyond their angles. It \A 

 directed obliquely downwards and outwards, resting on the deep muscles 

 and the angles of the ribs. The muscle is covered, excepting at its superior 

 border, by the rhomboid and levator anguli scapulae muscles. 



The serratus posticus inferior, broader and stronger than the preceding 

 muscle, passes outwards and upwards to the four lowest ribs ; it arises, 

 by a thin aponeurotic membrane, which forms part of the posterior layer of 

 the lumbar aponeurosin, from the spinous processes and interspinous liga- 

 ments of the two last dorsal and two or three upper lumbar vertebrae. 

 The outer part of the muscle forms a fleshy lamella inserted by four digita- 

 tions into the lower burder of the last four ribs. The uppermost of those 

 digitations is very broad, and covers in part the second ; the last, varying 

 in size with the length of the twelfth rib, is entirely concealed by the rest 

 of the muscle (see fig. 171, p. 202). The serratus inferior is covered by 

 the latissimus dorsi, and its aponeurotic part is firmly united for some 

 distance with the tendon of that muscle. 



Fig. 190. DORSAL MUS- 

 CLES OF THE UPPER 

 PART OF THE TRUNK. 



I, first ; VI, sixth dor- 

 sal vertebra ; 1 , upper part 

 of the complexus major 

 muscle ; 2, splenius capi- 

 tis ; 3, 3', splenius colli ; 

 4, serratus posticus supe- 

 rior ; 5, upper part of the 

 longissimus dorsi ; 5', the 

 same continued up on the 

 left side into the transver- 

 saliscervicis ; 5", 5", on the 

 right side the transversa- 

 lis cervicis spread out 

 from its attachments ; 6, 

 upper insertions of the 

 sacro-lumbalis and acces- 

 sorius ; 6', the same con- 

 tinued up on the left side 

 into the asceudens cer- 

 vicis; 5", upper, 6", lower 

 end of the ascendens cer- 

 vicis of the right side 

 spread out from its attach- 

 ments ; 7, small part of 

 the spinalis dorsi ; 8, 

 right levator anguli sca- 

 pulae, dissected out from 

 its attachments ; 8', on 

 the left side, the upper 

 part of the levator sea- 

 pulse, shown in its relation to the splenius colli ; 

 on the right side. 



Fig. 190. 



three of the levatores costarurn shown 



