HISTOLOGY. 113 



The sinus of the kidney is formed by the union of the 

 excretory duct and is lined with white fibrous tissue of 

 the tubules, and is continuous with the ureters. 



Hirer cise No. 61. Make sections of the tissue given 

 you and study, mount and preserve. 



URETERS. 



The ureters are the two tubes that convey the urine 

 from the kidneys to the bladder and are composed of 

 three coats ; viz : mucous, muscular and fibrous. They 

 are lined with squamous cells. 



THE BLADDER. 



The bladder is composed of the same number of 

 coats as the ureters. It is lined with squamous cells. 



THE URETHRA. 



The urethra consists of two coats lined in different 

 parts with different cells in the prostatic portion with 

 transitional cells; the middle portion with stratified 

 columnar; and in the penile portion with columnar 

 cells. 



