442 



THE URINARY SYSTEM 



vessel which, after leaving the corpuscle, promptly breaks into a second 

 capillary plexus about the adjacent tubules. 



The efferent vessels of those glomeruli which lie in that portion of 

 the cortex adjoining the medulla, frequently pass to the boundary zone 

 of the latter region where they form the arteria 1 recta? spuriae which, 

 though lacking a true arterial structure they possess no circular mus- 



f* ^gys? - 



"aJM* I* ." 



----- * 



FIG. 408. FROM THE CORTEX OF THE HUMAN KIDNEY. 



The blood-vessels have been injected and appear dark. A cortical ray and the 

 adjacent labyrinth is included, a, cortical ray; b, a glomerulus in the labyrinth. 

 Moderately magnified. (After Disse.) 



cle fibers pursue the same course as the true arteriolas rectae and assist 

 the latter in supplying the capillary plexus of the medulla. The medul- 

 lary capillaries, like those of the rays in the cortex, form a network with 

 elongated meshes which surround the parallel tubules of this region. 

 The capillaries of the cortical labyrinth, being distributed among irregu- 

 lar tortuous tubules, possess a more polygonal mesh. 



The iuterlobular veins begin near the surface of the organ where 



