278 THE HUMAN BODY. 



APPENDIX TO CHAPTER XVIII. 



To demonstrate the anatomy of the renal organs proceed as 

 follows : 



1. Kill a rat in any merciful way; placing it under a bell-jar 

 with a sponge soaked in ether is a good method. 



2. Open the abdomen of the animal, remove its alimentary canal, 

 and cut away (with stout scissors) the ventral portion of the pelvic 

 girdle. The dark-red kidneys will then be easily recognized on each 

 side of the dorsal part of the abdominal cavity, the right one nearer 

 the head than the left. 



3. Dissect away neatly the connective tissue, etc., in front of the 

 vertebral column, so as to clean the inferior vena cava and the abdom- 

 inal aorta. Trace out the renal arteries and veins. 



4. Find the ureter, a slender tube passing back from the kidney 

 towards the pelvis : it leaves the inner border of the kidney behind 

 the vein and artery; and lying, at first, at some distance from* the 

 middle line, converges towards its fellow as it passes back. 



5. Follow the ureters back until they reach the urinary bladder; 

 dissect away the tissues around the latter and note its form, etc. 



6. Open the bladder ; find the apertures of entry of the ureters, 

 and pass bristles through them into those tubes. Note the mucous 

 membrane lining the bladder. 



7. Remove one kidney from the body and divide it from its outer 

 to near its inner border ; turn the two halves apart (still leaving them 

 connected by the tissues at the inner border), and examine the cut 

 surfaces. 



8. Note at the inner border (Jiilus) the dilatation (pelvis) of the 

 ureter; the outer, darker, granular cortical portion of the kidney, and 

 the inner, paler, smoother medullary poi'tion; the papilla formed by 

 a projection of the medullary substance at the hilus, contained in an 

 expansion (calyx) of the pelvis of the ureter. 



9. Obtain a fresh sheep's kidney. Divide it by a section made 

 through it from its outer to its inner border. On the cut surfaces the 

 cortex and medulla will be more readily demonstrated than on the 

 rat's kidney. The pyramids of MalpigM will also be easily seen, and 

 the offshoots of the cortex extending between them. 



