238 THE MICROSCOPIST. 



urinary examinations, but the foregoing will be found of 

 practical use to the student. 



Microscopic deposits in urine are either organic fixtures 

 or precipitates from solution. They should be collected 

 by standing several hours in a conical vessel. 



1. Organic Mixtures. (1.) Epithelium. The character 

 of the scales will serve often to show the locality of dis- 

 ease in the urinary organs. The appearance of cells from 

 various parts is shown in Fig. 142. 



(2.) Mucus and pus-cells. Mucus is deposited as a floc- 

 culent cloud, entangling a few round or oval delicately 

 granular cells, a little larger than a red blood-globule. 

 In disease this increases and contains numerous ill-defined 

 cells. A very thick glairy deposit in disease of the blad- 

 der may be mistaken for mucus, although it is pus altered 

 by the action of carbonate of ammonia. 



As pus is often formed from the germinal matter of 

 epithelial cells, a small quantity in the urine is not neces- 

 sarily a sign of serious disease. In large quantities, pus 

 forms an opaque cream-colored deposit, which becomes 

 glairy and tenacious on the addition of liquor potassse. 

 Pus-globules under the microscope, if long removed from 

 the body, are granular, and show from one to four nuclei 

 when treated with acetic acid. In fresh pus-corpuscles, 

 especially in warm weather, amoeboid motion is often seen. 

 In a late period of catarrh of the bladder, but little epi- 

 thelium will accompany the discharge, but crystals of 

 triple phosphates generally occur in pus derived from the 

 bladder. 



(3.) Blood-disks usually form a reddish-brown deposit. 

 A smoky appearance of the urine is produced in blood 

 derived from the kidney. A brown deposit resembling 

 blood, but showing granules and no disks, is supposed to 

 be derived from blood. The epithelium associated with 

 blood-disks will often point out the source of haemorrhage. 



(4.) Spermatozoa in urine are not uncommon in perfect 



