chap, xviii.] THE SPERMATIC CORD. 371 



below Poupart's ligament be tickled the testicle of the 

 same side will usually be seen to be suddenly drawn 

 upwards. ' The tickling concerns the crural branch of 

 the genito-crural, while the motor nerve of the cre- 

 master is the genital division of the same trunk. The 

 interval of time that elapses between the irritation of 

 the skin and the movement of the testicle has been 

 appealed to as affording evidence of the state of nerve 

 health and of the readiness with which nerve impulses 

 are conducted. The three arteries of the cord are 

 divided in castration, and may all require ligature. 

 It is advisable to secure them separately, rather than, 

 adopt the clumsy plan of involving the whole cord 

 in one common ligature. The veins of the spermatic 

 or pampiniform plexus are very frequently varicose, 

 and then constitute the affection known as varico- 

 cele. Many anatomical causes render these veins 

 liable to this affection : they occupy a dependent 

 position, and the main vein is of considerable length, 

 and follows a nearly vertical course ; the vessels are 

 very large when compared with the corresponding 

 artery, and so the vis a tergo must be reduced to 

 a minimum ; they occupy a loose tissue, and are 

 lacking in support and in the aid afforded to other 

 veins (as in the limbs) by muscular contraction ; they 

 are very tortuous, form many anastomoses, and have 

 few and imperfect valves ; they are exposed to pres- 

 sure in their passage through the inguinal canal. The 

 left veins are more frequently affected than the right. 

 This may be explained by the facts that the left tes- 

 ticle hangs lower than the right; the left spermatic vein 

 enters the left renal at a right angle, while the right 

 spermatic vein passes obliquely into the vena cava ; 

 the left vein passes beneath the sigmoid flexure, and 

 is thus exposed to pressure from the contents of that 

 bowel. The relation between constipation and left- 

 sided varicocele is well known. 



