ANATOMY OF THE KIDNEYS. 159 



tral vessel. This arrangement gives to the vessels of the 

 fibrous envelope of the kidney a peculiar stellate appear- 

 ance. These are sometimes called the stars of Yerheyen. 

 The large trunks which form the centres of these stars then 

 pass through the cortical substance to the rounded bases of 

 the pyramids, where they form a vaulted venous plexus cor- 

 responding to the arterial plexus already described. The 

 vessels distributed upon the straight tubes of the pyramidal 

 substance form a loose plexus around these tubes, except at 

 the papillae, where the net-work is much closer. They then 

 pass into the plexus at the bases of the pyramids to join with 

 the veins from the cortical substance. " From this plexus a 

 number of larger trunks arise and pass toward the hilum 

 in the centre of the inter-pyramidal substance, enveloped 

 in the same sheath with the arteries. Passing thus to the 

 pelvis of the kidney, the veins converge into from three 

 to four great branches, which unite to form the renal, or 

 emulgent vein. A preparation of all the vessels of the kid- 

 neys shows that the veins are much more voluminous than 

 the arteries. 1 



The lymphatics of the kidney are few, and, according to 

 Sappey, only exist in the substance of the organ, converging 

 toward the hilum. This author does not admit the exist- 

 ence of superficial lymphatics. 



The nerves are quite numerous, and are derived from the 

 solar plexus, their filaments following the artery in its dis- 

 tribution in the interior of the organ and ramifying upon 

 the walls of the vessels. 



1 In a recent pamphlet on a circulation peculiar to the kidney of mammals, 

 a French author assumes to have demonstrated an arrangement of blood- 

 vessels in the cortical substance very different from that which we have de- 

 scribed. The glandular character of the Malpighian bodies and their connec- 

 tion with the convoluted tubes are denied. There is apparently so little basis 

 for these peculiar views, that it does not seem necessary to discuss them in 

 detail, and we will simply refer the reader to the original monograph. (SUCQUET, 

 Ifune circulation du sang specials au rein des animaux vertebres mammif&res, et 

 de la secretion des urines qiCelle y produit, Paris, 1867.) 



