72 EQUINE ANATOMY. 



of perforatus, and is attached by means of plantar aponeurosis 

 into semi-lunar crest of os pedis. 



Action. — Flexes third phalanx and also whole foot. 



Nerve. — Ulnar. 



ANTERIOR FOOT. 



They comprise two lumbricales and two interossei. 



LUMBRICALI. 



Origin. — From right and left side of perforans tendon. 

 Insertion. — Into fibrous tissue of the fetlock. 



INTEROSSEI. 



Origin. — Anteriorly between metacarpal bones. 

 Insertion. — Into anterior extensor of phalanges. 

 Action. — With extensor. 

 Nerve. — Ulnar. 



POSTERIOR EXTREMITY. 



Pelvic Region. — great psoas. 



Origin. — From bodies of last two dorsal and first five lumbar 

 vertebrae, inferior surface of last two ribs and lumbar transverse 

 processes. 



Insertion. — Internal trochanter. 



Action. — Flexor and external rotator of thigh. 



Nerve. — Iliaco-muscular. 



iLio psoas. 



Origin. — Whole iliac surface, external iHac angle, sacro-iliac 

 ligament and ilio-pectineal crest. 

 Insertion. — With preceding. 

 Action. — Same. 

 Nerve. — Iliaco-muscular. 



SMALL psoas. 



Origin. — Bodies of three or four last dorsal and all lumbar ver- 

 tebrae. 



hisertion. — Iho-pectineal eminence and ilio-lumbar aponeu- 

 rosis. 



Action. — Flexes pelvis on spine, or spine on pelvis. 



Nerve. — Iliaco-muscular. 



