COVERINGS OF THE TESTES. 739 



The anterior and lateral surfaces, as well as both extremities of the organ, are 

 convex, free, smooth, and invested by a serous covering called the tunica vaginalis. 

 The posterior border, to which the cord is attached, receives only a partial invest- 

 ment from this membrane. Lying upon the outer edge of this border, is a long, 

 narrow, flattened body, named, from its relation to the testis, the epididymis (int. 

 aiSujuo;, testis). It consists of a central portion or body, an upper enlarged ex- 

 tremity, the globus major or head ; and a lower pointed extremity, the tail or 

 globus minor. The globus major is intimately connected with the upper end of 

 the testicle by means of its efferent ducts ; and the globus minor is connected 

 with its lower end by cellular tissue, and a reflection of the tunica vaginalis. The 

 outer surface and upper and lower ends of the epididymis are free and covered by 

 serous membrane ; the body is also completely invested by it, excepting along its 

 posterior border, and connected to the back of the testis by a fold of the serous 

 membrane. Attached to the upper end of the testis, or to the epididymis, is a 

 small pedunculated body, the use of which is unknown. 



Size and Weight. The average dimensions of this gland are from one and a 

 half to two inches in length, one inch in breadth, and an inch and a quarter in 

 the antero-posterior diameter ; and the weight varies from six to eight drachms, 

 the left testicle being a little the larger. 



Coverings. At an early period of foetal life, the testes are contained in the abdo- 

 minal cavity, behind the peritoneum. Before birth, they descend to the inguinal 

 canal, along which they pass with the spermatic cord, and, emerging at the external 

 abdominal ring, they descend into the scrotum, becoming invested in their course 

 by numerous coverings, derived from the serous, muscular, and fibrous layers of 

 the abdominal parietes, as well as by the scrotum. The coverings of the testis 

 are the 



Skin ) Q 



> Scrotum. 

 Dartos ) 



Intercolumnar or External spermatic fascia. 



Cremaster muscle. 



Infundibuliforrn fascia, Fascia propria or Internal spermatic fascia. 



Tunica vaginalis. 



The SCROTUM is a cutaneous pouch, which contains the testes and part of the 

 spermatic cords. It is divided into two lateral halves, by a median line or raphe, 

 which is continued forwards along the under surface of the penis, and backwards 

 along the middle line of the perineum to the anus. Of these two lateral portions, 

 the left is longer than the right, and corresponds with the greater length of the 

 spermatic cord on the left side. Its external aspect varies under different 

 circumstances ; thus, under the influence of warmth, and in old and debilitated 

 persons, it becomes elongated and flaccid ; but, under the influence of cold, and 

 in the young and robust, it is short, corrugated, and closely applied to the testes 



The scrotum consists of two layers, the integument and the dartos. 



The integument is very thin, of a brownish color, and generally thrown into 

 folds or rugoe. It is provided with sebaceous follicles, the secretion of which haa 

 a peculiar odor, and is beset with thinly-scattered, crisp hairs, the roots of which 

 are seen through the skin. 



The dartos is a thin layer of loose reddish tissue, endowed with contractility ; 

 it forms the proper tunic of the scrotum, is continuous, around the base of the 

 scrotum, with the superficial fascia of the groin, perineum, and inner side of the 

 thighs, and sends inwards a distinct septum, septum scroti, which divides it into 

 two cavities for the two testes, the septum extending between the raphe and under 

 surface of the penis, as far as its root. 



The dartos is closely united to the skin externally, but connected with the 

 subjacent parts by delicate areolar tissue, upon which it glides with the greatest 

 facility. The dartos is very vascular, and consists of a loose areolar tissue, con- 

 taining unstriped muscular fibre. Its contractility is slow, and excited by cold 

 and mechanical stimuli, but not by electricity. 



