TESTES. 539 



rest, and is named the lacuna magna. In a beautiful preparation 

 of this lacuna, made by Sir Astley Cooper, the extremity of the 

 canal presents several large primary ramifications. 



TESTES. 



The testes are two small glandular organs suspended from the 

 abdomen by the spermatic cords, and enclosed in an external tegu- 

 mentary covering, the scrotum. 



The Scrotum is distinguished into two lateral halves or hemi- 

 spheres by a raph,e, which is continued anteriorly along the under 

 surface of the penis, and posteriorly along the middle line of the 

 perineum to the anus. Of these two lateral portions the left is some- 

 what longer than the right, and corresponds with the greater length 

 of the spermatic cord on the left side. 



The scrotum is composed of two layers, the integument and a 

 proper covering, the dartos ; the integument is extremely thin, 

 transparent, and. abundant, and beset by a number of hairs which 

 issue obliquely from the skin, and have prominent roots. The dartos 

 is a thin layer of a peculiar contractile fibrous tissue, intermediate 

 in properties between muscular fibre and elastic tissue ; it forms the 

 proper tunic of the scrotum, and sends inwards a distinct septum 

 (septum scroti) which divides it into two cavities for the two testes. 

 The dartos is continuous around the base of the scrotum with the 

 common superficial fascia of the abdomen and perineum. 



The Spermatic cord is the medium of communication between the 

 testes and the interior of the abdomen ; it is composed of arteries, 

 veins, lymphatics, nerves, the excretory duct of the testicle and its 

 proper coverings. It commences at the internal abdominal ring, 

 where the vessels of which it is composed converge, and passes 

 obliquely along the spermatic canal ; the cord then escapes at the 

 external abdominal ring and descends through the scrotum to the 

 posterior border of the testicle. The left cord is somewhat longer 

 than the right, and permits the left testicle to reach a lower level 

 than the right. 



The Arteries of the spermatic cord are the spermatic artery from 

 the aorta ; the deferential artery, accompanying the vas deferens, 

 from the superior vesical; and the cremasteric branch from the 

 epigastric artery. The spermatic veins form a plexus which con- 

 stitutes the chief bulk of the cord ; they are provided with valves at 

 short intervals, and the smaller veins have a peculiar tendril-like 

 arrangement which has obtained for them the name of vasa pampi- 

 niformia. The lymphatics are of large size, and terminate in the 

 lumbar glands. The nerves are the spermatic plexus, which is 

 derived from the aortic and renal plexus, the genital branch of the 

 genito-crural nerve, and the scrotal branch of the ilio-scrotal. 



The Vas deferens, the excretory duct of the testicle, it situated 

 along the posterior border of the cord, where it may be easily dis- 

 tinguished by the hard and cordy sensation which it communicates 



