448 A MANUAL OF ANATOMY. 



joined tendon arch over the spermatic cord (or round liga- 

 ment). 



In the angle between the external and internal oblique 

 muscles is seen the cord (or round ligament) resting upon 

 Poupart's ligament, and disappearing under the arching 

 fibres above mentioned. The space occupied by the cord or 

 round ligament is the inguinal canal. (Fig. 91.) The same 

 remarks apply to this canal that were made in reference to 

 the abdominal rings it is not a canal except when made 

 such by a hernia or by the dissector. It is a " potential" 

 canal. It extends from the internal to the external abdom- 

 inal rings, a distance of one and one-half inches. The floor 

 is formed by Poupart's ligament, upon which the cord is 

 seen to rest. In front is the aponeurosis of the external 

 oblique ; behind, the conjoined tendon, internal oblique, and 

 fascia of the transversalis (will be seen later). Above, at 

 outer part, the muscular arch of the two internal muscles. 



As the cord is examined, it will be found covered with 

 detached loops of muscular fibres, which are reflected upon 

 it in gradually lengthened festoons as low as the testicle. 

 These muscular loops constitute the cremaster muscle, and 

 with the connective tissue binding the loops together is 

 known as the crenaasteric fascia. The cremaster mus- 

 cle is usually described as detached portions of the internal 

 oblique. Some fibres no doubt come from this source, and 

 some from the foetal structure called the gubernaculum. 

 See page 460. 



The cremaster is supplied by the genitocrural nerve. 

 There is neither cremaster muscle nor fascia in the female. 



The ilio-inguinal nerve (Fig. 92) can be traced from 

 where it passed through the external ring, upward and out- 

 ward until it disappears through the internal oblique and 

 transversalis. It lies close to Poupart's ligament. 



