475 



they pass among the tubules of the cortex, and there again form a 

 second capillary system which anastomoses with the capillary system 



FIG. 23lA. DIAGRAM OF COURSE OF Two FIG. 231s. DIAGRAM' OF DISTRIBUTION 

 URINIFEROUS TUBULES. (Klein.) OF BLOODVESSELS IN HUMAN KIDNEY. 



./, cortex ; B, boundary zone ; G, papillary ( Ludwig. ) 



zone of medulla ; aa', superficial and at, Interlobular arteries ; ci, interlobular 

 deep layers of cortex free from glome- veins ; g, glomerulus ; -t-s, stellate vein ; 



ruli. nr, vr, arteri?e and venre rectse forming 



bundles ; ab, vb ; up, venous plexus in 

 the papillae. 



of the medulla. Both systems then join to form the efferent veins, 

 Avhich anastomose in the boundary zone, whence larger veins run 



