296 The Abdomen 



median line ; and, as the child lies supine, one's fingers may be thrust 

 inwards through the chink. 



The viscera immediately behind the linea alba are the left lobe 

 of the liver, stomach, transverse colon, great omentum, small intestine 

 and mesentery, and the distended bladder or pregnant uterus. 



The linea semilunaris marks the splitting of the aponeurosis of 

 the internal oblique along the outer border of the rectus ; it extends 

 from the eighth costal cartilage to the outer end of the pubic crest. 

 Like the ' white line,' it possesses neither muscular fibres nor blood- 

 vessels ; it is the site of puncture when the ascitic patient is tapped 

 lying upon his side ; in that position the fluid falls against the one 

 flank, whilst the intestines float against the other and are thus out of 

 the way of the trocar. Through the linea semilunaris also the kidney 

 may be conveniently reached in the transperitoneal operation, or the 

 stomach opened. 



Xiineae transversae. Extending across the recti are several ten- 

 dinous intersections which show on the surface of a well-developed man 

 as slight depressions crossing from the white to the semilunar line ; 

 quadrilateral segments of the muscle stand in relief between them. 

 One of the lines is at the level of the umbilicus, one at the ensiform 

 cartilage, and a third midway between them. Sometimes a fourth is 

 found between the navel and the pubes. Occasionally a segment of 

 muscle between two of the lines has been mistaken for abscess or 

 tumour, and in hysterical subjects irregular contraction in them may 

 produce a variety of 'phantom tumour! ^ 



In a fat subject two transverse creases intersect the linea alba : one 

 at the umbilicus, the other a few inches above the pubes ; the bladder 

 may be conveniently tapped at the spot where the lower furrow crosses 

 the middle line. These furrows are the result of a folding of the front 

 of the abdomen in leaning forward and stooping, a certain amount of 

 the fat being absorbed by the constant pressure. 



The superficial fascia consists of a fatty and of a deeper, mem- 

 branous layer, between which the main tributaries of the superficial 

 blood-vessels and the lymphatic glands are placed. The superficial 

 layer has slight connection with the abdominal aponeurosis except at 

 the umbilicus. In the female, just above the pubes, an extra deposit 

 of fat in the subcutaneous tissue produces an elevation, the mons 

 veneris. 



The deeper layer of the superficial fascia is a firm, thin sheet, which, 

 coming on either side from the thoracic and lumbar regions, is attached 

 to the iliac crests, and along Poupart's ligament down to the pubic 

 spines. Thence it passes in a loose investment around the spermatic 

 cord, and helps in the formation of the scrotum. From the back 

 of the scrotum the membrane runs on to the outer lip of the pubic and 

 ischial rami (covering the crus and erector penis), and eventually 

 joins the base of the triangular ligament. On the median side of 



