158 



EXCKETION. 



The efferent vessels, immediately after their emergence 

 from the capsule, break up into a very fine and delicate 

 plexus of capillaries, closely surrounding the convoluted 

 tubes. These form a true plexus, the branches anastomosing 

 freely in every direction ; and the distribution of vessels in 



this part resembles 

 essentially the vascu- 

 lar arrangement in 

 the glands generally. 

 Bowman has called 

 the branches which 

 connect together the 

 vessels of the Mal- 

 pighian tuft and the 

 capillary plexus sur- 

 rounding the tubes, 

 the portal system of 

 the kidney. 1 These 

 intermediate vessels 

 form a coarse plexus 

 around the prolonga- 

 tions of the pyramids 

 of Ferrein into the 

 cortical substance. 

 The renal or emul- 



Malptehian bodies, injected, and convoluted tubes from gent Vein takes its Ol'i- 

 the kidney of the sheep. (Is AACS, Structure and Phys- . . , ,1 



iology of the Kidney. Transactions of the New York gin, in part ironi the 

 Academy of Medicine, 1857, vol. i., p. 391.) .,, n 



capillary plexus sur- 

 rounding the convoluted tubes, and in part from the vessels 

 distributed in the pyramidal substance. A few branches 

 come from vessels in the envelopes of the kidney, but these 

 are comparatively unimportant. The plexus surrounding 

 the convoluted tubes empties into venous radicles, which 

 pass to the surface of the kidney, and these present a num- 

 ber of little radiating groups, each converging toward a cen- 



1 BOWMAN, op. cit., p. 63. 



