544 



MUSCLES OF THE ABDOMEN. 



and tendinous posteriorly, from the external half or third 

 FIG. 169. j of Poupart's ligament, and ten- 



dinous and fleshy from the in- 

 ner surfaces of the cartilages 

 of the six or seven lower ribs. 

 These fibres all end in a tendon, 

 which near the linea semilunaris, 

 unites with the posterior layer 

 of the internal oblique, and is 

 inserted into the ensiform car til- 

 age, the whole length of the linea 

 alba, the upper margin of the 

 pubis, and the linea innominata- 

 This tendon passes behind the 

 rectus, except about midway be- 

 tween the pubis and umbilicus, 

 where the whole pass in front. 

 The union of this tendon with 

 that of the internal oblique at 

 the crista of the pubis, receives 

 the name of the conjoined tendon which forms the floor of 

 the external ring. Function. -To compress the viscera and 

 aid in expiration. 



The rectus abdominis (Fig. 167) is exposed by a longitu- 

 dinal incision through the tendons of the broad muscles, 

 extending from the ensiform cartilage to the pubis, and 

 turning these tendons over to the linea semilunaris, when 

 both the recti muscles will be seen lying side by side, along 

 the median line. They are long and straight, thicker be- 

 low than above, and arise by a flat tendon from the supe- 

 rior margin of the pubis between the symphysis and spine ; 

 the fibres ascend and are inserted into the ensiform carti- 

 lage, and cartilages of the fifth, sixth, and seventh ribs. 

 The recti are about three inches in breadth, and present, 



FIG. 169 represents the Transversalis Muscle, a Latissimus dorsi. 6 Ser- 

 ratus major anticus. c External oblique, d External intercostals. e Inter- 

 nal intercostals. / Transversalis abdominis. g Fascia lumborum. h Sheath 

 of the rectus, its posterior part, i Rectus abdominis cut off, and its sheath. 

 j Rectus abdominis of right side, k Crural arch. I Gluteus maximus. 



