EXCRETION 



453 



FIG. 171. -DIAGRAM OF 

 BLOODVESSELS OF KIDNEY 

 (KLEIN, AFTER LUDWIG). 



ai, interlobular artery ; vi, 

 interlobular vein ; g, glomer- 

 ulus, to which an afferent 

 artery is seen coming from the 

 interlobular artery, and from 

 which an efferent artery pro- 

 ceeds to break up into a capil- 

 lary network surrounding the 

 renal tubules ; vs, vena stel- 

 lata ; ar, arteriae rectae ; vb, 

 leash of venae rectae ; vp, vas- 

 cular network round ducts at 

 apex of a papilla. 



FIG. 172. DIAGRAM OF RENAL TUBULE 



(KLEIN). 



A, cortex ; a, layer of cortex immediately under 

 capsule containing no Malpighian corpuscles ; 

 a', inner layer of cortex devoid of Malpighian cor- 

 puscles ; B, boundary layer ; C, papillary zone of 

 medulla ; i, Bowman's capsule ; 2, neck of cap- 

 sule ; 3, proximal convoluted tubule ; 4, spiral 

 tubule ; 5, descending part of Henle's loop- 

 tubule ; 6, the loop ; 7, 8, and 9, ascending limb 

 of loop -tub ule ; 10, irregular tubule; n, distal 

 convoluted tubule ; 12, junctional tubule ; 13, 

 collecting tubule, in a medullary ray or pyra- 

 mid of Ferrein 14, collecting tubule in the 

 boundary layer ; 15, large collecting tubule 

 ending in a duct of Bellini. 



