PHYSIOLOGICAL ANATOMY OF THE KIDNEYS. 



363 



present enlargements at irregular intervals in their course. The narrow por- 

 tions are about j-^ of an inch (12 p) in diameter, and the wide portions, 



FIG. 116. Structure of the kidney (Landois). 



I, blood-vessels and tubes (semi-diagrammatic). A, capillaries of the cortical substance ; B, capillaries 



of the medullary substance ; 1. artery penetrating a Malpighian body ; 2, vein emerging from a 



Malpighian body ; R, arteriolae rectae ; c, venae rectae ; v, v, interlobular veins ; s, stellate veins ; 



I, i, capsules of Miiller ; x, x, convoluted tubes ; T, T, T. tubes of Henle ; N, N, N, N, communicating 



tubes ; o, o, straight tubes ; O, opening into the pelvis of the kidney. 



IT, Malpighian body. A, artery ; E, vein ; c, capillaries ; K, epithelium of the capsule ; H, beginning of 

 a convoluted tube. 



III, rodded cells from a convoluted tube. 1, view from the surface ; 2, side view (o, granular zone). 



IV, cells lining the tubes of Henle. 



V, cells lining the communicating tubes. 



VI, section of a straight tube. 



about twice this size. The narrow portion is lined by small, clear cells 

 with very prominent nuclei. The wider portions are lined by larger, gran- 



