EXCRETION. 



477 



outward into the cortex. At the base of the pyramids branches of the 

 arteries form an anastomosing plexus. From this plexus vessels are given 

 off, some of which follow the straight tubules torwad th apexeof the pyramids, 



Lobule. 



Lobule. 



.Thin 



division of the 

 loop of Henle. 



"N,. Tunica albuginea. 



Stellate vein. 



Interlobular 



artery. 



Interlobular 



vein 



, Arcif orm artery 



Arcitorm vein. 



Interlobar artery. 



Interlobar vein. 



Papillary duct. - 



FIG. 217. SCHEME OF THE COURSE OF THE URINIFEROUS TUBULES AND THE RENAL 



VESSELS. 



vasa recta, while others enter the cortex and pass to its surface (Fig. 218). 

 In the course of the latter small branches are given off, each of which soon 

 divides and subdivides to form a ball of capillary vessels known as the glomer- 



