CREMASTER. TRANSVERSALIS. 215 



The CREMASTER, considered as a distinct muscle, arises from the 

 middle of Poupart's ligament, and forms a series of loops upon 

 the spermatic cord. A few of its fibres are inserted into the tu- 

 nica vaginalis, the rest ascend along the inner side of the cord, to 

 be inserted, with the conjoined tendon, into the pectineal line of the 

 os pubis. 



Relations. The internal oblique is in relation by its external surface 

 with the external oblique, latissimus dorsi, spermatic cord, and external 

 abdominal ring. By its internal surface with the transversalis muscle, 

 the fascia transversalis, the internal abdominal ring, and spermatic 

 cord. By its lower and arched border with the spermatic cord, form- 

 ing the upper boundary of the spermatic canal. 



The cremaster is in relation by its external surface with the aponeu- 

 rosis of the external oblique and inter- columnar fascia ; and by its in- 

 ternal surface with the fascia propria of the spermatic cord. 



The internal oblique muscle is to be removed by separating it from 

 its attachments to the ribs above, and to the crest of the ilium and 

 Poupart's ligament below. It should be divided behind by a vertical 

 incision extending from the last rib to the crest of the ilium, as its 

 lumbar attachment cannot at present be examined. The muscle is 

 then to be turned forwards. Some degree of care will be required in 

 performing this dissection from the difficulty of distinguishing between 

 this muscle and the one beneath. A thin layer of cellular tissue is all 

 that separates them for the greater part of their extent. Near the 

 crest of the ilium the circumflexa ilii artery ascends between the two 

 muscles, and forms a valuable guide to their separation. Just above 

 Poupart's ligament they are so closely connected that it is impossible 

 to divide them. 



The TRANSVERSALIS is the internal flat muscle of the abdomen ; it 

 is transverse in the direction of its fibres, as is implied in its name. 

 It arises from the outer third of Poupart's ligament, from the internal 

 lip of the crest of the ilium, its anterior two-thirds ; from the spinous 

 and transverse processes of the lumbar vertebrae, and from the inner 

 surfaces of the six inferior ribs, indigitating with the diaphragm. Its 

 lower fibres curve downwards, to be inserted, with the lower fibres of 

 the internal oblique, into the pectineal line, and form the conjoined 

 tendon. Throughout the rest of its extent it is inserted into the 

 crest of the os pubis and linea alba. The lower fourth of its aponeurosis 



superior or internal pillar ; the margin below the ring, the inferior or external 

 pillar; the curved intercolumnar fibres are seen proceeding upwards from Pou- 

 part's ligament to strengthen the ring. The numbers 14 and 15 are situated 

 upon the fascia lata of the thigh ; the opening immediately to the right of 15 is 

 the saphenous opening. 16. The rectus muscle of the right side brought into 

 view by the removal of the anterior segment of its sheath : * the posterior seg- 

 ment of its sheath with the divided edge of the anterior segment. 17. The 

 pyramidalis muscle. 18. The internal oblique muscle. 19. The conjoined 

 tendon of the internal oblique and transversalis descending behind Poupart's 

 ligament to the pectineal line. 20. The arch formed between the lower curved 

 border of the internal oblique muscle and Poupart's ligament; it is beneath this 

 arch that the spermatic cord and hernia pass. 



