FASCIA OF THE ABDOMEN. 545 



three or four irregular transverse lines, which are tendin- 

 ous intersections of these muscles, and called linece trans- 

 verses Their situations correspond to the umbilicus, the 

 ensiform cartilage, midway these two latter points, and 

 sometimes helow the navel. These lines adhere strongly 

 to the tendons, and linea alba in front, and are not 

 often seen on the back of these muscles. Function. To 

 bring the chest and pelvis toward each other and compress 

 the bowels. 



The pyramidalis , (Fig. 167,) situated at the lower part of 

 the abdomen, is a short muscle and arises by a broad, fleshy, 

 and tendinous base, from the superior border of the sym- 

 physis, extending to the spine of the pubis, having the rec- 

 tus behind, and the external oblique in front. Its fibres 

 ascend in a tapering manner, and are inserted into the linea 

 alba, halfway between the pubis and umbilicus. This mus- 

 cle is placed- in a sheath between the tendons of the broad 

 muscles, and is not unfrequently absent. Function. To as- 

 sist the rectus, and make tense the linea alba. 



The conjoint action of all these muscles is to lessen the 

 cavity of the abdomen and compress the viscera, and, al- 

 though they are voluntary muscles, and also aid in expi- 

 ration, defecation, vomiting, and parturition, they do some- 

 times act without the consciousness of the individual, and 

 are referred to by Mr. Harrison as strong examples of the 

 influence of the excito-motory nerves, in consequence of 

 their sympathy with the lungs, larynx, stomach, bladder, 

 and uterus, sympathies which cannot be traced to any 

 direct nervous connection. 



Fasciae of the Anterior and Lateral Walls. The fascia 

 superficialis and the fascia transversalis. 



The superficial fascia is sub-cutaneous, and continuous 

 with that covering the chest. It consists of condensed cel- 

 lular structure, and is variable in consistency in different 

 parts being weak, and cellular in some, and aponeurotic 

 in others. It is traced over the abdominal muscles below, 

 to Poupart's ligament, to which it slightly adheres and 

 thence upon the thigh for a short distance also upon the 

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