424 



THE URINARY APPARATUS. 



Portion of tubule. 



Nature of epithelium. 



Position of tubule. 



Capsule 



First convoluted tube . 



Spiral tube 



Small or descending) 



tube of Henle. . . . j 



Loop of Henle 



Larger or ascending \ 



tube of Henle. . . . j 



Zigzag tube 



Second convoluted tube 



Junctional tube . . . . 



Straight or collecting) 



tube j 



Duct of Bellini . 



/ Flattened, reflected over glom- ) 

 1 erulus. j 



f Cubical, fibrillated, the cells > 

 \ interlocking. j 



Cubical, fibrillated (like the last). 



Clear flattened cells. 



Like the last. 



f Cubical, fibrillated, sometimes ) 

 \ imbricated. f 



(Cells strongly fibrillated;) 

 < varying height ; lumen > 

 ( small. 



f Similar to first convoluted 

 tube, but cells are longer, 

 with larger nuclei, and they 

 have a more refractive as- 

 pect. 



Clear, flattened, and cubical cells. 



/Clear cubical and columnar) 



\ cells. j 



Clear columnar cells. 



Labyrinth of cortex. 



Labyrinth of cortex. 



Medullary ray of cortex. 

 / Boundary zone and partly 

 | papillary zone of medulla. 



Papillary zone of medulla. 

 /Medulla and medullary ray 

 I of cortex. 



Labyrinth of cortex. 



Labyrinth of cortex. 



f Labyrinth passing to medul- 

 \ lary ray. 



Medullary ray and medulla. 

 Opens at apex of papilla. 



Blood-vessels. The renal artery (Fig. 238), which supplies the 

 kidney, is a branch of the abdominal aorta, which before entering 



FIG. 241. From section of cortical substance of human kidney : a, epithelium 

 of Bowman's capsule ; 6 and d, membrana propria ; c, glomerular epithelium ; e, 

 blood-vessels; /, lobe of the glomerulus; g, commencement of uriniferous tubule; 

 h, epithelium of the neck ; i, epithelium of proximal convoluted tubule ; X 240 

 (Bohm and Davidoff). 



