STUDY of THE KIDNEY OF TEE SHEEP. 85 



sion in the kidney to which the tubes pass 

 is called the hilum.) 

 B. Gross structure of the kidney. 



1. Pull apart the halves of the kidney suffi- 



ciently to look within. 



2. What is the shape of the cavity near the 



hilum '(sinus of the kidney)? 



3. By means of a probe locate the tube (ureter) 



which passes out from this cavity. 



4. The layer on the outside of the kidney sec- 



tion is called the cortical layer. 



a. Does this layer anywhere reach down 



to the sinus? 



b. What characteristics distinguish the 



cortical layer from the rest of the 

 solid portion of the kidney? 

 5- The bodies which form the medullary por- 

 tion of the kidney within the cortical 

 layer are called the pyramids of Malpighi. 



a. Why is the name pyramid given to 



them? 



b. Do these pyramids project into the 



sinus of the kidney? 



c. Press one of the pyramids of Malpighi. 



Can you see any substance ooze 

 out? 



