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THE UEINARY SYSTEM 



cuboidal cells, or thick flattened plates, whose form varies with the state 

 of distention of the organ, and whose deep surfaces are indented by the 

 rounded ends of the pear-shaped cells which form the deeper layers. The 

 deepest cells are smaller and are irregularly spheroidal in shape. They 



FIG. 411. TRANSECTION OF HUMAN URETER. 

 Hematein and eosin. Photo. X 113. 



are firmly attached to the underlying connective tissue which here and 

 there projects into the epithelial layer carrying with it the most super- 

 ficial capillary vessels. The cells of the deeper layers divide by karyo- 

 kinesis and push toward the surface to replace the more superficial cells 

 which are gradually desquamated. Direct cell division occurs in the 



