EXTERIOR OF PELVIS, ETC. 197 



particularly, the genito-urinary apparatus, the termina- 

 tion of the bowel and its inferior boundary, the perineal, 

 and the anal regions. Those considerations of its anat- 

 omy which more particularly concern the accoucheur, 

 may be advantageously referred to special works upon 

 the subject, such as its various measurements, &c. 



Its walls present surgically two surfaces for examina- 

 tion, on either of which operative proceedings may be 

 instituted (1) An external, partly free, consisting infe- 

 riorly of the perineum, laterally of a region belonging 

 partially to the lower limb, and posteriorly, of the sacral 

 and coccygeal region ; and (2) an internal, consisting of 

 the peritoneal surface of the perineum, and soft parts 

 lining its bony structure, which include the pelvic vis- 

 cera and the great vessels. 



The external genitals may be regarded as appendages 

 to the pelvis, and will be conveniently treated of before 

 entering upon its immediate anatomy, and such parts of 

 its lateral boundary as are evidently common to it and 

 to the lower limb will be included in the description of 

 the latter. 



EXTERIOR OF PELVIS PELVI-PERINEAL REGION. 

 SURGICAL ANATOMY OF THE SCROTUM. 



Structure. The various tissues entering into the struc- 

 ture of the scrotum are met with on dissection in the 

 following order : The skin, very thin, lax, and rugose ; 

 the superficial fascia, with which it is closely associated, 

 continuous with that covering the abdomen and peri- 

 neum, and is in this region entirely destitute of fat. 

 The dartos, consisting of loose areolar tissue, in which is 

 a considerable amount of unstriped muscular fibre, very 



17 



