LATERAL OPERATION FOR LITHOTOMY. 



1015 



the forceps is introduced. The same measure may be resorted to afterwards 

 should much resistance be experienced when the foreign body is being ex- 

 tracted. Lastly, this part of the operation (the extraction of the stone) 



Fig. 713. 



Fig. 718. VlEW OP THE DISTRIBUTION OF THE ARTERIES TO THE VlSCERA OP THE MALE 

 PELVIS, AS SEEN ON THE REMOVAL OP THE LEFT Os INNOAIINATUM, &C. (from R. Quain). \ 



a, left external oblique muscle of the abdomen divided ; 6, internal oblique ; c, trans- 

 versalis ; d, d, the parts of the rectus muscle divided and separated ; e, psoas magnus 

 muscle divided ; /, placed on the left auricular surface of the sacrum, points by a line to 

 tbe sacral plexus of nerves ; </, placed on the os pubis, sawn through a little to the left of 

 the symphysis, points to tbe divided spermatic cord ; A, the cut root of the crus penis ; 

 i, the bulb of the urethra ; k, elliptical sphincter ani muscle ; I, a portion of the ischium 

 near the spinous process, to which is attached the short sacro-sciatic ligament ; m, the 

 parietal peritoneum ; , the upper part of the urinary bladder; n, n', the left vas deferens 

 descending towards the vesicula seminalis ; n", the left ureter ; o, the intestines ; 1, the 

 common iliac at the place of its division into external and internal iliac arteries ; 2, left 

 external iliac artery ; 3, internal iliac ; 4, obliterated hypogastric artery, over which the 

 vas defereus is seen passing, with the superior vesical artery below it ; 5, middle vesical 

 artery ; 6, inferior vesical artery, giving branches to the bladder, and descending on the 

 prostate gland and to the back of the pubes ; 7, placed on the sacral plexus, points to the 

 common trunk of the pudic and sciatic arteries ; close above 7, the gluteal artery is seen 

 cut short ; 8, sciatic artery cut short as it is escaping from the pelvis ; 9, placed on the 

 rectum, points to the pudic artery as it is about to pass behind the spine of the ischium ; 

 9', on the lower part of the rectum, points to the inferior haemorrhoidal branches ; 9", 

 on the perinseum, indicates the superficial perineal branches ; 9'", placed on the prostate 

 gland, marks the pudic artery as it gives off the arteries of the bulb and of the crus peuis ; 

 10, placed on the middle part of the rectum, indicates the superior hsernorrhoidal arteries 

 as they descend upon that viscus. 



should be conducted slowly, so as gradually to dilate the parts without lace- 

 rating them ; and the forceps should be held with its blades one above the 

 other. 



The Structures divided in the Operation. In the first incision the integu- 

 ment and ihe subjacent fatty layer are divided ; afterwards a small part 



