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. 



Insej'tion. — 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. 

 Nerz'e. — Intercostal s. 



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. 



