810 MALE ORGANS OF GENERATION. 



oval extremity or body, and a long slender caudal filament. A small circular 

 spot is observed in the centre of the body, and at its point of connection with the 

 tail there is frequently seen a projecting rim or collar. The movements of these 

 bodies are remarkable, and consist of a lashing or undulatory motion of the tail. 



DESCENT OF THE TESTES. 



The testes, at an early period of foetal life, are placed at the back part of the 

 abdominal cavity, behind the peritoneum, in front and a little below the kid- 

 neys. The anterior surface and sides are invested by peritoneum ; the blood- 

 vessels and efferent ducts are connected with their posterior surface; and 

 attached to the lower end is a peculiar structure, the gubernaculum testis, which 

 is said to assist in their descent. 



The Gubernaculum Testis attains its full development between the fifth and 

 sixth months ; it is a conical-shaped cord, attached above to the lower end of 

 the epididymis, and below to the bottom of the scrotum. It is placed behind 

 the peritoneum, lying upon the front of the Psoas muscle, and completely filling 

 the inguinal canal. It consists of a soft transparent areolar tissue within, which 

 often appears partially hollow, surrounded by a layer of striped muscular fibres, 

 the Cremaster, which ascends upon this body to be attached to the testis. 

 According to Mr. Curling, the gubernaculum, as well as these muscular fibres, 

 divides below into three processes ; the external and broadest process is con- 

 nected with Poupart's ligament in the inguinal canal ; the middle process descends 

 along the inguinal canal to the bottom of the scrotum, where it joins the dartos ; 

 the internal one is firmly attached to the os pubis and sheath of the Rectus 

 muscle; some fibres, moreover, are reflected from the Internal Oblique on to 

 the front of the gubernaculum. Up to the fifth month, the testis is situated in 

 the lumbar region, covered in front and at the sides by peritoneum, and sup- 

 ported in its position by a fold of that membrane, called the mesorchium ; between 

 the fifth and sixth months the testis descends to the iliac fossa, the gubernaculum 

 at the same time becoming shortened ; during the seventh month, it enters the 

 internal abdominal ring, a small pouch of peritoneum (processus vaginalis} pre- 

 ceding the testis in its course through the canal. By the end of the eighth month, 

 the testis has descended into the scrotum, carrying down with it a lengthened 

 pouch of peritoneum, which communicates by its upper extremity with the 

 peritoneal cavity. Just before birth, the upper part of this pouch usually 

 becomes closed, and this obliteration extends gradually downwards to within a 

 short distance of the testis. The process of peritoneum surrounding the testis, 

 which is now entirely cut off from the general peritoneal cavity, constitutes the 

 tunica, vaginatis. 1 



Mr. Curling believes that the descent of the testis is effected by means of the 

 muscular fibres of the gubernaculum ; those fibres which proceed from Poupart s 

 ligament and theObliquusInternus are said to guide the organ into the inguinal 

 canal ; those attached to the pubis draw it below the external abdominal ring ; 

 and those attached to the bottom of the scrotum complete its descent. During 

 the descent of the organ these muscular fibres become gradually everted, form- 

 ing a muscular layer, which becomes placed external to the process of the peri- 

 toneum, surrounding the gland and spermatic cord, and constitutes the Cremaster. 

 In the female, a small cord, corresponding to the gubernaculum in the male, 

 descends to the inguinal region, and ultimately forms the round ligament of the 

 uterus. A pouch of peritoneum accompanies it along the inguinal canal, 

 analogous to the processus vaginalis in the male ; it is called the canal of Nuck. 



1 The obliteration of the process of peritoneum which accompanies the cord, and is hence 

 called the funicular process, is often incomplete. For an account of the various conditions 

 produced by such incomplete obliteration (which are of great importance in the pathological 

 anatomy of Inguinal Hernia), the student is referred to the Essay on Hernia, by Mr. Birkett, in 

 "A System of Surgery," edited by T. Holmes, vol. iv. 



