ABDOMINAL FASCIiE. 



315 



part on each side, of three layers of muscle, the fibres of which run in 

 different directions ; those of the two most superficial layers being 

 oblique, and those of the innermost layer being transverse. In fi'ont 

 those three layers of muscle are replaced by tendinous expansions, which 

 meet in the middle line ; on either side of that line the fibres of the 

 recti muscles extend in a vertical direction between the tendinous 

 layers, supported usually at the lower end by the pyramidales muscles. 

 Posteriorly the wall is formed in part by aponeurosis, and in part by 

 muscles of wiiich the fibres are chiefly vertical, viz., the muscles of the 

 back, and in IVont of them the quadratus lumborum. 



Fig. 223. 



Fig. 223.— Superficial \iew of the Muscles ov tue Abdomen, from before. 



(A. T.) A 



14, external oblique muscle ; 15, is placed on the ensifonn cartilage at tlie upper end 

 of the Imea alba ; 15, umbilicus; 16, symphysis pubis at the lower end of the linea 

 alba ; above 16, the pyivimidales muscles are seen shining throu^'h the abdominal 

 aponeurosis ; from the upper 1 4 to 1 7, the linea semilunaris ; between this line and the linea 

 alba are seen the transverse lines of the rectus muscle ; above 22 the curved margin of 

 Poupart's ligament ; on either side of 16, the external abdominal ring is indicated. 



The abdominis escternus obliquus muscle arises from the outer 



