152 SPECIAL ANATOMY. 



263. 5. Pyramidalis abdominis. 



Pos. : before the inferior extremity of the preceding muscle, 

 close to the linea alba, covered by the anterior layer of its sheath. 

 Or. : Symphys. pubis (the superior border) ; broad. Ins. : Linea 

 alba, between umbilicus sm&symphysis; pointed. Use: to stretch 

 linea alba. 



Nerves: (fourth to fifth) iliohypogastricus. 



264. 6. Cremaster s. tunica erythroides. 



Pos. : in front and on the side of the spermatic cord (in the 

 canal inguinalis) ; thin, long. Or. : Spina pubis and M. obliq. 

 intern. Ins.: Tunica vaginal, commun.funical. sperm, et tes- 

 ticuli. Use : to draw the testicle upwards, pressing the spermatic 

 cord. 



265. 7. QuadrafMs lumborum. 



Pos. : along the lumbar vertebrae, in a strong tendinous sheath, 

 behind the kidneys, the colon, psoas and diaphragm muscles ; 

 between the Ilium and last rib ; covered behind by the tendon 

 of trans versalis. Or.: 1. Crista ilei labium intern, (the posterior 

 part); 2" broad ; 2. Lig. ileo-lumbale ; 3. Proc. transv. of the 

 lumbar vertebrae. Ins. : twelfth rib the inferior border of the 

 posterior extremity. Use : to draw the twelfth rib downwards 

 (exspiratio) ; inclining the vertebral column sideways, or the 

 pelvis. 



Nerves: lumbaks. 



266. 8. Diaphragma. 



This is the transverse, muscular, dome-shaped, vaulted partition 

 which separates the thoracic from the ventral cavity. It is ten- 

 dinous in the centre (pars tendinea}^ fleshy in the periphery (p. 

 carnosa), which is attached to the ribs (p. costal.) and to the 

 lumbar vertebrae (p. lumbal.). 



Attachments : a. the bodies of the second to the fourth lumbar 

 vertebrae (anterior surface). 



b. Sternum and Proc. ensiform. ; cartilage of the seventh to 

 the twelfth ribs (posterior surface). 



a. Pars lumbalis consists of six (three on each side) crura. 



a. Crura interna, strong, arise from the third to the fourth lumbar vertebrae ; 

 between them lies: 



aa. Hiatus aorticus (for aorta, ductus thoracicus, vena azygos), 3" long, \" 

 broad, rather to the left of the central line. 



The internal crura cross each other before the parts above mentioned, and 

 in this way form the 



#. Foramen cesophageum for the (oesophagus, nn. vagi, and continuation of 



