154 EQUINE ANATOMY. 



pubis, posteriorly it divides and gives origin to the 

 crural aponeurosis and the crural arch. Action : Ex- 

 piratory. 



Internal crtjbal aponeurosis. — Lines the internal 

 face of the leg, covering the muscles of that re- 

 gion. 



Crural arch, Fallopius or Poupart's ligament. — 

 Extends from the anterior border of the pubis to the 

 external angle of the ilium. Inside of the pectineal 

 insertion of the small psoas muscle it forms the anterior 

 line of the crural ring. 



Inguinal canal. — An inf undibuliform canal through 

 which the means of support for the testicles or the 

 external mammary vessels pass from the abdomen. It 

 presents a superior and an inferior opening. 



4. Small or internal oblique of the abdomen. — 

 Synonyms. Ilio-abdominalis, (G). Obliquus internus 

 abdominis, (1*). Structure : like the preceding. Attach- 

 ments : Fleshy portion, to the external angle of the 

 ilium and the crural arch ; aponeurotic portion, to the 

 internal face of the cartilages of the false ribs, and the 

 linea<ilba. Action: Expiratory. 



5. Great straight of the abdomen. — Synonyms. 

 Sterno-pubialis, (G). Rectus abdoniin is, (P). Attach- 

 ments : the cartilages of the four last sternal and first 

 asternal ribs, inferior face of the sternum, the internal 



