62 EQUINE ANATOMY. 



Insertion. Inferior tubercle of atlas. 

 Action. Whole muscle flexes neck. 

 Nerve. Third and fourth cervical. 



REGION OF BACK. 



TRAPEZIUS. 



Origin. Cervical cord and transverse processes of first dorsal 

 vertebrae. 



Insertion. Olecranian spine and scapular aponeurosis. 

 Action. Raises shoulder and carries it forward or backward. 

 Nerve. Spinal accessory. 



LATISSIMUS DORSI. 



Origin. Spinous processes of all lumbar and last fourteen or 

 fifteen dorsal vertebrae. 



Insertion. Internal tuberosity of body of humerus. 



Action. Carries arm backward and upward, also in forced in- 

 spiration. 



Nerve. Eighth cervical. 



SERRATUS ANTICUS MINOR. 



Origin. Dorsal spinous processes from second to thirteenth. 

 Insertion. External surface of ribs from fifth to fourteenth. 

 Action. Raises ribs in inspiration. 

 Nerve. Intercostals. 



SERRATUS POSTICUS MINOR. 



Origin. Spinous processes of dorsal vertebrae from tenth to 

 eighteenth, and few lumbar vertebrae. 



Insertion. External face of last nine ribs. 



Action. Draws ribs upward and backward in expiration. 



Nerve. Intercostals. 



ILIO-SPINALIS (LONGISSIMUS DORSI OF PERCIVAL). 



Origin. Lumbar border, external angle and internal surface 

 of ilium, and spinous processes of all lumbar, dorsal and last four 

 cervical vertebrae. 



