THE URIXARY SVSTT^^r 335 



Plexuses of fine non-medullated libres (sympathetic) accompany the 

 arteries to the glomeruli. Delicate terminals have been described as 

 passing from these plexuses, piercing the basemrnt luenibrane and 

 ending freely between the epithelial cells of the tubules. 



The Kidney-Pelvis and Ureter 



The kidney-pelvis, with its subdivisions the calyces, and the ureter 

 constitute the main excretory duct of the kidney. Their walls consist 

 of three coats: an inner mucous, a middle muscular, and an outer 

 fibrous. 







. cm c 



/ 



,. • /|. ;*;#%# if ^iS^'l^^s/ .■■::'^^^ • 



•:. . ^ .', 1 1 ^' #^^ #-^? %,;.|:^^ -.. ; I ; ■ . ^^ ,K \ ■ ; 



.■•>V^.^'v . .•; IPS' m p;-.^,^;->; 



Fig. 231. — Transverse Section of Human Ureter. (Prenant.) Z, lumen; c/), epi- 

 thelium; ch, stroma; cml, inner longitudinal muscular layer; cmc, outer circular 

 muscular layer; ad, fibrosa. X25. 



The mucosa is lined by epithelium of the transitional type (Fig. 

 231, cp). There are from four to eight layers of cells, the cell outlines 

 are usually well defined, and the surface cells instead of being dis- 

 tinctly squamous are only slightly flattened. Less commonly large 

 flat plate-like cells, each containing several nuclei, are present. The. 

 cells rest upon a basement membrane, beneath which is a stroma of 



