Chap, xviii.] THE SPERMATIC CORD. 413 



thumb and finger. Mr. Birketfc (Holmes' " System ") 

 gives three cases of rupture of the vas deferens during 

 severe and svidden exertion. The duct appears to 

 have in each case given way within the abdomen at 

 some point between the internal ring and the spot 

 where it approaches the ureter. The injury is 

 followed, as may be supposed, by atrophy of the 

 corresponding testicle. The size of cremaster muscle 

 depends mainly upon the weight it has to suspend. 

 In atrophy of the testicle it almost entirely disappears, 

 while in cases of large slow-growing tumours of the 

 gland it attains considerable proportions. If in 

 children or young adults the skin over the middle of 

 the thigh just 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 cremaster 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, 

 Of the arteries the spermatic comes from the aorta and 

 lies in front of the vas, the cremasteric arises from 

 the deep epigastric and lies among the superficial 

 layers of the cord in its outer segment, while the 

 deferential artery from the superior or inferior vesical 

 lies by the side of tho vas (Fig. 38). The first-named 

 vessel is the size of the posterior auricular, and the 

 two latter the size of the supraorbital. The three 

 arteries of the cord are divided in castration, and may 

 all require ligature. It is advisable to secure the 

 vessels in sections, rather than adopt the clumsy plan 

 of involving the whole cord in one common ligature. 

 The veins are divided roughly into two sets. The 

 anterior is by far the larger set, runs with the 



