430 



THE URINARY SYSTEM 



blood-vessels the capsule opens, through a narrow neck., into the first or 

 proximal convoluted portion of the uriniferous tubule. 



The glomerulus is a true arterial rete mirabile, since it receives an 

 afferent artery, which, after forming the capillaries of the glomerulus, 



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FIG. 402. FROM THE CORTICAL LABYRINTH (PARS CONVOLTJTA) OF THE HUMAN 

 KIDNEY. 



A large renal corpuscle is in the center of the figure. At its upper border are 

 several sections of distal convoluted tubules. The great majority of the tubules 

 shown are from the proximal convoluted portions, a, a portion of a glomerulus; 

 b-b, parietal layer of the capsule; c, proximal convoluted tubules; d, just within 

 this point is a transection of a junctional tubule having relatively low and clear 

 epithelium and a broad lumen. Hematein and eosin. Photo. X 135. 



passes out as an efferent artery to again enter a capillary plexus about 

 the neighboring tubules of the renal cortex. The afferent vessel is of 

 somewhat larger caliber than the efferent a noteworthy fact because of 

 its relation to the intraglomerular blood pressure. 



