STRUCTURE OF THE KIDNEY 



167 



FIG. 202. STRUCTURE OF THE EPITHELIUM OF THE CONVOLUTED TUBUL.ES. 



A, section of a convoluted tubule from the rat, showing the unaltered proto- 

 plasm occupying a circular area around the nucleus of each cell ; a, 6, c, 

 isolated cells from the convoluted tubules of the rat ; e, isolated cells from 

 the dog's kidney, viewed from the inner surface, and showing the irregular 

 contour of the protoplasm ; /, isolated cells from the newt, showing the 

 rods and the homogeneous cuticular layer. 



FIG. 203. PART OF A CON- 

 VOLUTED TUBULE FROM 

 THE DOG'S KIDNEY. 



FIG. 204. PORTIONS OF TUBULES, ISOLATED. 

 (Cadiat.) 



a, large collecting tubule ; 6, loop of Henle ; c, descending 

 tubule of Henle. 



