THE ABDOMEN 



655 



■understand this action, it is to be noted that the fibres of the internal 

 obHque of one side coincide in direction with those of the external 

 oblique of the opposite side. 



The most of the fibres pass upwards and forwards across those 

 of the external oblique, and coinciding with those of the internal 

 intercostal muscles. The Poupart fibres, however, pass downwards 

 and inwards, and join the corresponding fibres of the transversahs 



Pectoralis Major 



Lumbar Aponeurosis - |-~ [' 



—Middle Linea Transversa 



.- Obliquus Extemus 



Abdominis (reflected) 



Obliquus Intertills 

 Alxijminis 



''y" - Rectus Abdominis 



Anterior Superior Iliac Spine 



Poupart 's Ligament 



Fig. 284. — The Internal Oblique Muscle. 



abdominis to form the conjoined tendon. The aponeurosis is 

 broader above than below. Along the outer border of the rectus 

 abdominis, over about its upper three-fourths, it divides into two 

 laminae, one of which passes in front of the muscle and the other 

 behind it. The anterior lamina joins the aponeurosis of the external 

 oblique, and the posterior lamina joins the anterior aponeurosis of the 

 transversalis abdominis. It is this latter lamina which has an inser- 

 tion into the seventh and eighth costal cartilages and ensiform 



