ABDOMINAL WALL 407 



1. The external spermatic or intercolumnar fascia from the aponeurosis 



of the external oblique. 



2. The cremasteric fascia the muscular element of which is partly derived 



from the internal oblique. 



3. The infundibuliform fascia from the fascia transversalis. 



The dissector will find it difficult to demonstrate in every case these 

 different investments of the testis. In cases of large hernise of old standing, 

 however, they become thickened, and are more readily recognisable. In any 

 case the dissector works at a great disadvantage when he attempts to unfold 

 the coverings of the cord and unravel its constituent parts while they are 

 attached to the body. The cord and testis of the right side should be 

 removed by dividing the former with its coverings at the level of the sub- 

 cutaneous inguinal ring. The specimen should then be placed in a cork- 

 lined tray and dissected under water. Having fastened the cord and 

 testicle, with pins, to the bottom of the tray, little difficulty will be 

 experienced in displaying and recognising the different layers, and a 

 splendid demonstration will be afforded of the constituent parts of the cord. 



From the above description the student will understand 

 that there is only one tunic common to both testes viz. 

 the integument ; that the superficial fascia and dartos, forming 

 the dartos tunic, and the investments derived from the 

 abdominal wall, constitute special tunics for each testis. 



Funiculus Spermaticus (Spermatic Cord). The spermatic 

 cord is formed by the association together of certain blood- 

 vessels, nerves, and lymph vessels, along with the ductus 

 deferens, all of which are proceeding to or coming from the 

 testis. These structures come together at the abdominal 

 inguinal ring, and this may be taken as the point at which the 

 cord begins. It has already been traced in its course through 

 the inguinal canal, and has been observed to issue from it 

 through the subcutaneous inguinal ring. It is now seen as 

 it lies within the scrotum suspending the testicle. 



Before dissecting out the constituent parts of the cord, 

 examine the extra-peritoneal fatty tissue which lies behind 

 the abdominal inguinal ring. Note that a process of this 

 tissue is prolonged downwards with the cord. Now with 

 the handle of the knife gently separate the extra-peritoneal 

 fat from the subjacent peritoneum. Behind the abdominal 

 inguinal ring the peritoneum shows a slight bulging 

 forwards, and a slender fibrous band may be detected 

 passing into the cord from the most prominent part of this 

 bulging. This fibrous cord is the remains of the tube of 

 peritoneum which, in the foetus, connected the serous invest- 

 ment of the testicle (the tunica vaginalis) with the general 

 peritoneal lining of the abdomen. In some cases it may be 



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